.bash_prompt: Fix `parse_git_dirty` for Git v1.8.0+

Git 1.8.0+ says “nothing to commit (working directory clean)”.
Older Git versions return “nothing to commit (working directory clean)”.

Thanks to @nicolahery in #143 for the suggestion.
.aliases: Add `map`

Ref. #157.
.functions: Make `gz` more awesome
.aliases: Lowercase `com.apple.finder`

Hat tip: @alrra.
.osx: Show item info to the right of the icons on the desktop
.functions: Add `calc`
.bash_profile: Move the `LANG` & `LC_ALL` exports into `.exports`
.osx: Remove the iTunes Ping settings

Apple officially closed the iTunes Ping service on September 30th, 2012 (http://i.imgur.com/U7bHo.jpg).
.osx: Document the various values for Hot Corners settings
.osx: Clarify that the iTunes settings are for pre-iTunes 11 only
Merge remote-tracking branch 'upstream/master'

* upstream/master:
  .osx: Clarify that the iTunes settings are for pre-iTunes 11 only
  .osx: Document the various values for Hot Corners settings
  .osx: Remove the iTunes Ping settings
  .bash_profile: Move the `LANG` & `LC_ALL` exports into `.exports`
  .functions: Add `calc`
  .osx: Show item info to the right of the icons on the desktop
  .aliases: Lowercase `com.apple.finder`
  .functions: Make `gz` more awesome
  .aliases: Add `map`
  .bash_prompt: Fix `parse_git_dirty` for Git v1.8.0+