Update .vimrc

let g:jedi#usages_command = "<leader>z" is now depricated in jedi plugin. We should use g:jedi#usages_command instead
Merge pull request #1 from khorsmann/patch-1

Update .vimrc
Updated .vimrc

Thanks to christopherbridenstine for reporting this error and providing a patch.
.vimrc tweak to follow guideline

Minor tweak to follow guideline of 
"" when it should be deleted.

Small, but useful.
Merge pull request #3 from MichalPodeszwa/master

.vimrc tweak to follow guideline
Merge pull request #1 from mbrochh/master

update with original repo