Add browse-kill-ring package
Adds comments to sample modules.
Updates key chord bindings.
Merge pull request #457 from climatewarrior/updateKeyChords

Updates key chord bindings.
Merge pull request #456 from climatewarrior/add-module-docs

Adds comments to sample modules.
Enable browse-kill-ring's default keybindings
Improve prelude-eval-and-replace
Don't use C-x SPC as it's used in Emacs 24.4 by default for rectangular selection