Added a way for defining custom plugins

README.rst

@@ -7,4 +7,14 @@ of it.
 It uses `vim-plug`_ plugin manager, so after cloning, just open vim, and it
 will automatically install all the plugins.
 
+Other than that, there are two additional config files which can be added to
+the configuration as a local configuration files just to not mess up with main 
+config file. Both of them should be placed under ``$HOME/.vim`` directory.
+
+First one is ``vimrc.local``, which might contain additional/override options 
+for specific machine. 
+
+The other ``plugins.local`` and similarly there can be additional plugins 
+defined.
+
 .. _vim-plug: https://github.com/junegunn/vim-plug