Codemirror update to 3.19 latest (thanks marclaporte)

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/12.x@48740 b456876b-0849-0410-b77d-98878d47e9d5
[FIX] Codemirror now contains a Tiki mode, but it's out of date, so remove the packaged one in case it's causing any conflicts.

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/12.x@48741 b456876b-0849-0410-b77d-98878d47e9d5
[FIX] Use posix-compliant syntax

git-svn-id: file:///var/local/code.tiki.org/tikisvn/branches/12.x@48745 b456876b-0849-0410-b77d-98878d47e9d5