.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
Merge remote-tracking branch 'upstream/master'

* upstream/master:
  bin: Update to Bash 4.2.42
  README: Update Lauri Ranta’s hidden preferences URL
  .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`