editor: check current ace version for bugs

The editing mode is somewhat strange in terms of default keyboard shortcuts and highlighting.
Check for new session or any other changed default options that might cause it.
Otherwise, consider a downgrade to v. 1.1.8 but then compatibility with requirejs must be granted.

(from redmine: issue id 2215, created on 2015-04-26 by root, closed on 2015-05-08)

• Changesets:
  • Revision 2185 by Thorben Quast on 2015-05-08T15:23:47Z:

editor: correct use of "line" state, fixes 'ACE bug', fix #2215

• Revision 2185 by Thorben Quast on 2015-05-08T15:23:47Z:

editor: correct use of "line" state, fixes 'ACE bug', fix #2215