Add ability for a per project .vimrc.local file

I was just thinking about this earlier today and then noticed on Twitter
that @garybernhardt was thinking the same thing. From some of the
replies to his tweet, I came up wtih this. Adding a .vimrc.local file to
the CWD where vim is opened will cause it to be source, meaning custom
key bindings can be applied on a per project basis.

vim/vimrc.symlink

@@ -331,3 +331,11 @@ let g:ctrlp_custom_ignore = '\.git$|\.hg$|\.svn$'
 if filereadable(glob("~/.vimrc.local"))
     source ~/.vimrc.local
 endif
+
+"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
+" => Local, Per Project vimrc
+"""""""""""""""""""""""""""""""""""""""""""""""""""""""""""
+
+if filereadable(".vimrc.local")
+    source ./.vimrc.local
+endif