Initial commit of settings for @alextalks

- Ignore local modifications
- Added configs for:
    - ack
    - bash
    - gvim
- Updated configs for:
    - vim
    - git
    - osx
- Don't install homebrew
- Don't install python
- Disable ZSH configs by default

Change-Id: I57836a369b29b64881a77c17cabc5494c9795867