Added a mapping (,z) to quick correct spellings.

Uses the first suggestion.
Added some spellings to the dictionary.
Added the hard mode bundle.

Use ,h to toggle it.
Removed the arrow key noops, that's what hard mode is for.
Enabled hard mode by default.
Corrected the hard mode auto command.
Improved the speed status line change speed.
Swapped the powerline bundle to the new version.