[Fix #426] Remove M-O keybinding

It caused problems in terminals.
Merge branch 'master' of github.com:bbatsov/prelude
Cask files are Emacs Lisp files
Remove obsolete dep to git-commit-mode
Code style
Remove obsolete markdown module
Extract Helm support into a separate module
[Fix #399] Extract key-chord into a separate module
Fix a reference to nrepl.el
Some minor changes in yank-pop
Replace mentions of WikEmacs with EmacsWiki
Fix key-chord module commentary.
Merge pull request #439 from seanfisk/fix-key-chord-commentary

Fix key-chord module commentary.
[Fix #416] Add quotes to the alias examples
Merge branch 'master' of github.com:bbatsov/prelude
[Fix #436] Enable smartparens-mode in latex-mode
Use prelude-require-packages everywhere
[Fix #444] Add command prelude-update-packages
New keychord xx -> execute-extended-command
[Fix #447] Extract ido config into a module

This should make it simpler to disable ido completely if you want to use
an alternative library (like `icomplete` or `icicles` for instance).