Add missing API documentation for `IOutputExecutor.output` and fix the `output_` method signatures in the turnstile example.
Add a news fragment for this fix.

Hopefully this will feed into Twisted's `NewsBuilder` and make releases easier.
Worst case I'll manually concatenate a bunch of files...
Put the documentation in the conventional place - as parameter docs, not ivar docs.
Parameterize the output method prefix
Add a news fragment.
Have trivialInput produce an implementer of IRichInput, whose instances will be providers of IRichInput
Update the _FiniteStateInterpreter's receive docstring
Remove 'provider' in trivialInput, fix test case name, and add newsfile
Simplify.  I'll add real documentation for rich inputs real soon now, promise.
Merge pull request #11 from hybridcluster/rich-input-context-docs-9

Fix the `output_` signatures in the example to match what is actually required by machinist.
Mention that issues are tracked using waffle.io
Require and port to eliot 0.4.0.
document the change
remove an unused import
Merge pull request #15 from cyli/fix_trivial_input

Fix for trivialInput so that instances produced are providers of IRichInput
Merge pull request #22 from adamtheturtle/point-at-waffleio-21

Mention that issues are tracked using waffle.io
Merge pull request #24 from hybridlogic/eliot-update-5

Require and port to eliot 0.4.0.

Fixes #5.
Merge pull request #12 from hybridcluster/parameterize-output-prefix-10

Parameterize the output method prefix.
merge master