Move message view theme setting from message view menu to global prefs
by default.

The message view theme isn't something the user is likely to change on a
regular basis, so we don't need to clutter the message view menu with
this setting. The menu item can still be enabled for those who want it.
Remove text selection menu item for JB and higher.

Those versions have text selection support built-in (via long pressing
the WebView).
Allow changing the message composer theme (background and text color).
Convert theme setting value to an enum.
Compose: Don't just theme the editboxes, but the whole content (but not the actionbar)

This way also the From: selection, To:, Cc, and Bcc: are themed correctly.
It looks more homogeneous and is consistent with the looks of the MessageView.
Fix settings import/export
Add contact pictures to message list
Add setting to toggle contact pictures
Add setting for contact pictures to import/export code
Resize the contact picture bitmaps to the display size
Fix some display issues
Clean up drawable folders
Update res/values/strings.xml
Merge pull request #250 from rk4an/patch-1

fix a little typo in language file
Remove ugly (placeholder?) icons
Use new holo-themed icons when possible
Switch our font sizes to have a "default", which is the size described in the XML.
Unify the text field size setting code. We should put it in a better place
There's no good reason to exclude the Subject from the "full headers" view, especicially since we now play games with it sometimes showing up in the header and sometimes in the titlebar
relayout the message header area
move the To and Cc labels into their own Views; stop playing span games to style them