extensions REFACTOR rename lyext_plugin structure to lyplg_ext

Unify naming conventions with types plugins API
diff --git a/src/plugins_exts.c b/src/plugins_exts.c
index e3d3a09..92344cd 100644
--- a/src/plugins_exts.c
+++ b/src/plugins_exts.c
@@ -19,9 +19,9 @@
 #include <stdint.h>
 #include <string.h>
 
-extern struct lyext_plugin metadata_plugin; /* plugins_exts_metadata.c */
-extern struct lyext_plugin nacm_plugin;     /* plugins_exts_nacm.c */
-extern struct lyext_plugin yangdata_plugin; /* plugins_exts_yangdata.c */
+extern struct lyplg_ext metadata_plugin; /* plugins_exts_metadata.c */
+extern struct lyplg_ext nacm_plugin;     /* plugins_exts_nacm.c */
+extern struct lyplg_ext yangdata_plugin; /* plugins_exts_yangdata.c */
 
 /* internal libyang headers - do not make them accessible to the extension plugins in plugins_exts_*.c */
 #include "common.h"
@@ -32,7 +32,7 @@
 /**
  * @brief list of all extension plugins implemented internally
  */
-struct lyext_plugin_record lyext_plugins_internal[] = {
+struct lyplg_ext_record lyext_plugins_internal[] = {
     {"ietf-netconf-acm", "2012-02-22", "default-deny-write", &nacm_plugin},
     {"ietf-netconf-acm", "2018-02-14", "default-deny-write", &nacm_plugin},
     {"ietf-netconf-acm", "2012-02-22", "default-deny-all", &nacm_plugin},
@@ -44,7 +44,7 @@
 
 /* TODO support for external extension plugins */
 
-struct lyext_plugin *
+struct lyplg_ext *
 lyext_get_plugin(struct lysc_ext *ext)
 {
     for (uint8_t u = 0; lyext_plugins_internal[u].module; ++u) {
diff --git a/src/plugins_exts.h b/src/plugins_exts.h
index 0900fd2..16bbe0c 100644
--- a/src/plugins_exts.h
+++ b/src/plugins_exts.h
@@ -160,13 +160,13 @@
 /**
  * @brief Extension plugin implementing various aspects of a YANG extension
  */
-struct lyext_plugin {
+struct lyplg_ext {
     const char *id;                     /**< Plugin identification (mainly for distinguish incompatible versions of the plugins for external tools) */
     lyext_clb_compile compile;          /**< Callback to compile extension instance from the parsed data */
     lyext_clb_data_validation validate; /**< Callback to decide if data instance is valid according to the schema. */
     lyext_clb_schema_printer sprinter;  /**< Callback to print the compiled content (info format) of the extension instance */
     /* lyext_clb_data_printer dprinter; ? */
-    lyext_clb_free free;                /**< Free the extension instance specific data created by ::lyext_plugin.compile callback */
+    lyext_clb_free free;                /**< Free the extension instance specific data created by ::lyplg_ext.compile callback */
 };
 
 /**
diff --git a/src/plugins_exts_internal.h b/src/plugins_exts_internal.h
index 085e917..75bc3f1 100644
--- a/src/plugins_exts_internal.h
+++ b/src/plugins_exts_internal.h
@@ -23,7 +23,7 @@
 /**
  * @brief Record describing an implemented extension.
  */
-struct lyext_plugin_record {
+struct lyplg_ext_record {
     const char *module;          /**< name of the module where the extension is defined */
     const char *revision;        /**< optional module revision - if not specified, the plugin applies to any revision,
                                       which is not an optimal approach due to a possible future revisions of the module.
@@ -31,13 +31,13 @@
                                       different revision, but all with the same pointer to the plugin extension. The
                                       only valid use case for the NULL revision is the case the module has no revision. */
     const char *name;            /**< name of the extension */
-    struct lyext_plugin *plugin; /**< plugin for the extension */
+    struct lyplg_ext *plugin;    /**< plugin for the extension */
 };
 
 /**
  * @brief List of internally implemented extension plugins.
  */
-extern struct lyext_plugin_record lyext_plugins_internal[];
+extern struct lyplg_ext_record lyext_plugins_internal[];
 
 /**
  * @brief Index of Metadata's annotation extension plugin in lyext_plugins_internal
@@ -54,6 +54,6 @@
  *
  * @param[in] mod YANG module where the
  */
-struct lyext_plugin *lyext_get_plugin(struct lysc_ext *ext);
+struct lyplg_ext *lyext_get_plugin(struct lysc_ext *ext);
 
 #endif /* LY_PLUGINS_EXTS_INTERNAL_H_ */
diff --git a/src/plugins_exts_metadata.c b/src/plugins_exts_metadata.c
index 6edd60c..12b99e8 100644
--- a/src/plugins_exts_metadata.c
+++ b/src/plugins_exts_metadata.c
@@ -155,7 +155,7 @@
 /**
  * @brief Plugin for the Metadata's annotation extension
  */
-struct lyext_plugin metadata_plugin = {
+struct lyplg_ext metadata_plugin = {
     .id = "libyang 2 - metadata, version 1",
     .compile = &annotation_compile,
     .validate = NULL,
diff --git a/src/plugins_exts_nacm.c b/src/plugins_exts_nacm.c
index afec924..0dab1c2 100644
--- a/src/plugins_exts_nacm.c
+++ b/src/plugins_exts_nacm.c
@@ -152,7 +152,7 @@
 /**
  * @brief Plugin for the NACM's default-deny-write and default-deny-all extensions
  */
-struct lyext_plugin nacm_plugin = {
+struct lyplg_ext nacm_plugin = {
     .id = "libyang 2 - NACM, version 1",
     .compile = &nacm_compile,
     .validate = NULL,
diff --git a/src/plugins_exts_yangdata.c b/src/plugins_exts_yangdata.c
index 3742a2b..f06fd64 100644
--- a/src/plugins_exts_yangdata.c
+++ b/src/plugins_exts_yangdata.c
@@ -166,7 +166,7 @@
 /**
  * @brief Plugin for the yang-data extension
  */
-struct lyext_plugin yangdata_plugin = {
+struct lyplg_ext yangdata_plugin = {
     .id = "libyang 2 - yang-data, version 1",
     .compile = &yangdata_compile,
     .validate = NULL,
diff --git a/src/tree_schema.h b/src/tree_schema.h
index eae5386..01774f5 100644
--- a/src/tree_schema.h
+++ b/src/tree_schema.h
@@ -1385,7 +1385,7 @@
     const char *name;                /**< extension name */
     const char *argname;             /**< argument name, NULL if not specified */
     struct lysc_ext_instance *exts;  /**< list of the extension instances ([sized array](@ref sizedarrays)) */
-    struct lyext_plugin *plugin;     /**< Plugin implementing the specific extension */
+    struct lyplg_ext *plugin;        /**< Plugin implementing the specific extension */
     struct lys_module *module;       /**< module structure */
     uint32_t refcount;               /**< reference counter since extension definition is shared among all its instances */
     uint16_t flags;                  /**< LYS_STATUS_* value (@ref snodeflags) */