Update vim-improvements.vundle

This removes a redundant Bundle that already appears on line 9. This was throwing warnings for me whenever I started macvim.
Merge pull request #470 from martco/patch-1

Update vim-improvements.vundle
Decided disabling arrow keys was hurting new people too much
Remove duplicated plugin
Custom settings
Added vundles local backup
Add customizations
Added store for git
Added plugins
Added custom options
Added cucumber
Added cucumber"
Removed extra bundles
Added user
Added nvm
2 space tabs
Changed to use ksdiff