Update README build status to master,stable .

This repository has switched from a `develop=edge,master=stable` to
a `master=edge,stable=stable` structure.
Lock to Ruby 2.0.0 instead of 2.0.0-p0 .
Build against ruby-2.0.0,1.9.3 jruby-19mode (failok) rbx-19mode (failok).

Remove ruby-1.9.2 from build list.
Update gemspec metadata and lock to redis 3.x instead of 3.0.x .
Update README, adding badge.fury,codeclimate, rearranging.
Document ryespy mailing list.
Refactor to App instance, rather than Ryespy singletons.

Introduce `App`, and configure on an instance rather than `Ryespy`
itself, moving related code from `lib/ryespy.rb` to `lib/ryespy/app.rb`.
Pass config, redis connection, notifiers, and logger where necessary.

Also move some `Config` tests into new `App` tests.
Simplify internal Ryespy::X namespace calls to X, etc.
Tweak executable --help, --version display.
Merge branch 'refactor'
Install Mocha, loading test environment in test/helper.rb .

Also remove unused `test/ryespy_test.rb`.
Implement App#start,#stop , moving executable main loop.

Add `App#initialize`,`#start`,`#stop` for application run control, with
`#setup`,`#cleanup`,`#refresh_loop` hooks. Move main loop from executable
to `App#refresh_loop`, setting up listener outside of loop. Trap
`SIGINT`, calling `App#stop` for friendly shutdown. Wrap executable
within rescue for friendly reporting of large errors, using `--verbose`
to toggle stacktrace.

Note that much of this code is based on the run control implementation in
[sidekiq-spy](https://github.com/tiredpixel/sidekiq-spy) (MIT License).
Update README throughout, clarifying and simplifying many things.
Move listeners/ => listener/ and notifiers/ => notifier/ .

`Listener::FTP`, `Listener::IMAP` are named singularly, so should be in
`listener/`. Likewise for `Notifier::Sidekiq`, which should be in
`notifier/`.
Test Config,App , tweaking and adding tests throughout.
Move listener code App#setup => App#refresh_loop , closing connections.

Creating the listener within `App#setup` results in connections being
held open (and never properly released, coincidentally). Instead, create
listener within each run of `App#refresh_loop`, which is like it was
previous to the `App` implementation, only with better closing.

This necessitates adjusting tests to use a fake listener.
Build with redis-server service.
Test and alter Notifier::Sidekiq, removing #initialize rescue.

Whilst testing, the `Notifier::Sidekiq#initialize` `rescue` block was
noted and removed; it likely was added in error, as there is no reason
for it to rescue `Net::FTPError`, for example.
Silent noisy logging during App#start test.
Install sidekiq-spy in development.

This makes it easy to check Sidekiq queues have been notified. e.g.

    sidekiq-spy -n resque