Fixed typos and signal handler arguments in tutorial.
Fixed email address in AUTHORS.
Cleaning up timetag and clock functions.
Adding signal.update() functions with timetag arguments.
Fixed error in function documentation.
Use doubles for timetags in Python bindings.
Fixed function documentation for msig_update(); fixed some formatting, etc.
Moved tutorials to own folder in /doc, added versions for python and maxmsp.
Merge branch 'master' into instances4
Release active instances when signal is freed.