[ANN] Scheduler moved to GitHub pharo-contributions/Scheduler

Hi;

"Scheduler" ws migrated from SmalltalkHub to GitHub - it is an easy-to-use task
scheduler that can run arbitrary blocks. See attached image for a quick example.

A few things have been cleaned as well:

 - separate tests into own package
 - class comments
 - categorize classes and methods
 - fix lint problems
 - follow SUnit best practices (super tearDown, super setUp)
 - removed unnecessary "super new initialize" call on class side
 - add a Travis CI job
 - ...

  https://github.com/pharo-contributions/Scheduler

It is usable and working in recent Pharo versions

Enjoy!

Bye
T.