…ree non-terminals

…arser implementation

Sometimes recovery nodes start before the current location where
the parser failed to continue. Since the parser works with a
short queue of schedulede TODO's around the current cursor, we
might end up outside of this queue when recovering. This breaks
several unspecified invariants of the SGTBF implementations. For
now I added a detection that a recovery node is to be planned
before the currently retained history and filter that recovery
node. The next step will be to make sure backtracking over the
current location is made possible.

…er input locations)

… because the next parser loop iteration always wants to advance one character

…imizations

…e version of Rascal and (b) the edit command is wired to the edit IDEService

…t in the scheme by copyinhthe contents to a tmp file

…sts are executed

… at this point