Change indent/unindent behaviour in visual mode

After indenting/unindenting the selected lines of code, vim
deselects forcing the user to reapply the selection in order to
indent multiple times.

This remap fixes the problem.
Add numbers.vim to vundles.list

numbers.vim is a plugin that allows for easy switch between
absolute and relative line numbers.
A convenient shortcut: ,tn (toggle numbers) is provided to
switch between the two modes

Fixes #276
Merge branch 'master' into test

* master:
  Synced with upstream
  Fix
  Add numbers.vim to vundles.list
  Add fugitive navigation enhancements
  Change indent/unindent behaviour in visual mode
  Change installation script
  Fixing typo in the readme
  Updating the readme with the visual star search plugin
  Adding visual star search vundle
  Improving semicolon insertion at the end of the line