.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
README: Update Lauri Ranta’s hidden preferences URL

The previous URL now 404s.
bin: Update to Bash 4.2.42
Merging newest files from Matias' repo