Integrated spell checking

- inline spell highlighter. This requires WebKit 2.3 to work.

- Addition of a suggested replacement word list to the context menu,
  for the word right clicked on

- A standard modeless spell check dialog that works on the current
  editable text (or selection).
  Heavily cribbed from Dawit's work on kdewebkitpart.

BUG: 305720
CCMAIL: lindsay.mathieson@gmail.com
REVIEW: 106417
REVIEWED-BY: adjam