Fixing a typo.
Merge pull request #216 from seanhussey/master

Fixing a typo.
Use FOCUSED_FILE_PATH constant instead of explicit file name
Remove :notification option
Rename Focuser formatter to just Formatter
DRY default options with Guard::RSpec::DEFAULT_OPTIONS
Write rspec summary info to ./tmp/rspec_guard_result
Refactor Runner + Inspector bunch totally

* Split single Inspector class to subclasses FocusedInspector,
  KeepingInspector, SimpleInsector with base class Inspectors::Base.
  Instanciate inspector using Inspectors::Factory.

  That's allow us to move logic of 'focus_on_failed' and 'keep_failed'
  to FocusedInspector and KeepingInspector accordingly.

* Move all notification code to separate class (Guard::RSpec::Notifier).

* Move responsibility of reading ./tmp/rspec_guard_result to Runner.
Return 'notification' option with default value of true
Formatter does notrequire Guard::RSpec to be fully loaded
Fix problem with success notifications when there are error + pending

RegExp used to find count of errors is failing when there is no pendings
because "(2 pending)" block in summary is optional.