v0.8

SprayCC is functional, stable, and performant such that I use it daily for builds and test runs.

What's missing:

• Error reporting could be better. The messages are typically reasonable, but just trigger a scary looking panic message.
• Shutdown execution engines in cluster if the jobs are terminated instead of waiting for the tasks to finish.
• Queue prioritization based on historical completion times.
• Better documentation and wide usage outside of just me.
• More complete unit test coverage.