allows multiple chunking results to be returned
added an option container to allow calling microplanning with different criteria
some documentation update
Check for guile-2.2 as well as 2.0
Whoops - remove incorrect check.

Its racey, there could be a king by the time this runs.
And that's just fine.
Merge pull request #1133 from williampma/microplanning

Microplanning: framework for returning multiple chunking results
SchemeEval: document sync and asynch usage.

The class provides both synchronous and asynchronous API's.
Add a note that explains this.