(1) Add UI controls for `keyMap`, `tabSize`, `indentWithTabs`, and
`lineWrapping`; `indentUnit` tracks `tabSize`.
(2) Dispatch `change` events from `loadPrefs` to initialize CM options
from the controls' event listener.
(3) Move stock options from the `CM.fromTextArea` call into `CM.defaults`.
Add `CM.setOption` method, analogous to the instance method, which updates
`CM.defaults` and sets the option in all instances; add `CM.getOption`
which simply returns `CM.defaults[option]`.
(4) Move the new editor functions into `CM.commands` and replace the
functions with commands.
Two independent filters. One allows only styles that are enabled, the
other allows only styles that were written locally (that is, styles
without an update URL).
F3, Shift-F3, Ctrl-H - find/find previous/replace
Ctrl-G: go to line dialog
Alt-PgDn: next code section
Alt-PgUp: previous code section
...and many more.
