Import replxx

Change-Id: Iffb9eb32eecb19b018ce353af7109a2bb1c68cf3
diff --git a/.gitmodules b/.gitmodules
index 3a4470e..9b5f9e4 100644
--- a/.gitmodules
+++ b/.gitmodules
@@ -22,3 +22,6 @@
 [submodule "submodules/libredblack"]
 	path = submodules/libredblack
 	url = ../../github/sysrepo/libredblack
+[submodule "submodules/replxx"]
+	path = submodules/replxx
+	url = ../../github/AmokHuginnsson/replxx