Added Dispatcher::setListenerFilter

Added a way of filtering listener methods that are registered to listen
for events using a regular expression.
Fix up event dispatcher unit test.
Merge pull request #269 from eddieajau/Dispatcher

Added Dispatcher::setListenerFilter
Allows the DI container to set a callable value.
Update documentation for the new feature.
Modify code per feedback.
Merge pull request #278 from eddieajau/DI

Allow the DI container to set a callable.
Don't load phputf8 if it has already been loaded
Merge pull request #281 from ianmacl/duplicate_phputf8

Don't load phputf8 if it has already been loaded
Use Regex backreference for same tags
Use DOTALL Regex modifier for multi-line strings
Remove duplicated variable (property of ColorProcessor)
ColorProcessor docblocks and codestyle
Fix a failing unit test
Merge pull request #286 from elkuku/ut-1

Fix a failing unit test
corrected docblock
More docblocks corrections
Updating Readme
corrections to update
Massive round of cleanup