className dropped by CodeMirror, need to pick up "error" from type
As it may not be there, we need to test for its existence and it's also
be part of a string eg "tag brackets error", so indexOf is needed
setLine deprecated, now need to use replaceRange and pass 2 objects for
start & end (line & ch)
getSelection needs "around" param as default is now "end"
Using commentChar now to handle char used on commenting (# or % for
Erlang)
Erlang, Julia, Java and YAML commenting covered
Include Python also as forgotten
adjustCursor to be set to 1 on single chars, overriding 2
Cursor adjusting done here now, not in parent function anymore as
adjustCursor value not available from that scope
