Split path_ into schemaPath_ and dataPath_

This change is necessary because different commands accept different
kinds of paths (for example "cd" only accepts a data path, on the other
hand "ls" doesn't care about data, so it accepts both). One option was to
create a new path struct for every command, but that could get quickly
out of control as new commands get added. The other option was define only
the data path and schema path and then change the commands' grammars, so
that they only accept the relevant paths, but in the end always return a
data path or a schema path.

Change-Id: I7668a446fbf674c7a5deae22d9aacdfb3da9b07e
diff --git a/src/parser.hpp b/src/parser.hpp
index 0318733..013a2f4 100644
--- a/src/parser.hpp
+++ b/src/parser.hpp
@@ -27,11 +27,11 @@
 public:
     Parser(const std::shared_ptr<const Schema> schema);
     command_ parseCommand(const std::string& line, std::ostream& errorStream);
-    void changeNode(const path_& name);
+    void changeNode(const dataPath_& name);
     std::string currentNode() const;
-    std::set<std::string> availableNodes(const boost::optional<path_>& path, const Recursion& option) const;
+    std::set<std::string> availableNodes(const boost::optional<dataPath_>& path, const Recursion& option) const;
 
 private:
     const std::shared_ptr<const Schema> m_schema;
-    path_ m_curDir;
+    dataPath_ m_curDir;
 };