PEP8 compliance

That extra line was breaking the build.
Merge pull request #1 from amarandon/before_signal_hook

Remove a blank line that's breaking the Travis build
started a supervisor page
remove all parenthesis here as @tarekziade proposed
Merge pull request #539 from thefab/before_signal_hook

Add before_signal and after_signal hooks
Update supervisor.rst

Fixed some typos & added references
Removed Travis skips
Merge pull request #541 from mozilla-services/travis-skip

Removed Travis skips
more details on supervisor streams