Added a debug sponsor with injectable dispatch and delivery mechanisms.
Actor creation is injectable.

Debug sponsor is 'control' sponsor. Added mechanism for injecting
how configuration should be constructed. README updates. Removed
previous tracing from core and put it in 'examples/tracing.js'.

The tests that were tied to tart.tracing are now using the
'examples/tracing.js' example. This should probably be refactored
to a separate module in the future.
README updates.
Added tart.control usage example to README.
Added output sample to tart.control usage in README.
Added 'npm run inject-examples' script to the project.
Tart sponsor factory has function(options) signature.
Modified signatures of tart.control pluggable functions.
tart.control() is tart.pluggable().
tart.sponsor() is tart.minimal().
Added 'npm run pluggable' example script to the project.
Merge pull request #7 from organix/general-mechanism

Implemented general pluggable mechanism.