Update libraries.conf for a new version of pathdir

The pathdir extension has been updated to version 5.2.0.

Author: cstaelin

libraries.conf

@@ -197,9 +197,10 @@ If you’d like to know more about matrices and how they can be used, you might
  {
     name: "Pathdir"
     codeName: "pathdir"
-    shortDescription: "Some useful operations on files and directories"
-    longDescription: "Pathdir provides tools for finding the name of the current model, the current working, user and model directories; creating, moving, renaming, identifying and deleting directories; and listing the contents of directories. Pathdir also allows one to find the size and modification date of files."
-    version: "5.1.0"
+    shortDescription: "Some useful operations on files and directories, and primitives for reading environment variables and system properties"
+    longDescription: "Pathdir provides tools for finding the name of the current model, the current working, user and model directories; creating, moving, renaming, identifying and deleting directories; and listing the contents of directories. Pathdir also allows one to find the size and modification date of files, and the values of both environment variables and system
+	properties."
+    version: "5.2.0"
     homepage: "https://github.com/cstaelin/Pathdir-Extension"
   }
   {