Add toString method to HTTPResponse / HTTPRequest for user convenience
Unittests script was wrong \(my bad\)
Enable Task.join/interrupt to work outside of the event loop for tasks of the same thread. See #443.

This makes it possible to use those functions outside of a task before the event loop has started, or when the event loop is manually run using processEvents().
fix issue #653
Merge pull request #651 from BoapNet/fix-tests

Fix unittests
Merge pull request #654 from japplegame/fix#653

Enable BSON serialization of const objects with toBson() methods. Fixes #653.
Add unit test for serializing const objects to BSON. See #654.
Use HTTPRequest / HTTPResponse toString methods
Minor typos
Merge pull request #650 from BoapNet/pretty-printer

Add toString to http.common.HTTPRequest / HTTPResponse
Finally we just need to compile it as PIC