Switch to PSR-4 to simplify directory structure.
Merge pull request #23 from nubs/psr-4

Switch to PSR-4 to simplify directory structure.
Update BoolTest to use @coversDefaultClass in phpdoc
Add trueValues and falseValues params to Boolean::filter()
Merge pull request #24 from chadicus/bools

Add custom bool values to Bool::filter
Update the README with examples of each of our filters.

Having to track through the files to view all the different filters
wasn't particularly fun, especially with the aliased names being
specified in another file entirely.

This should hopefully reduce the need to go to the code to figure out
what is available.
Merge pull request #25 from nubs/document-included-filters

Update the README with examples of each of our filters.
Fix some errors in the phpdocs.
Merge pull request #27 from nubs/phpdoc-errors

Fix some errors in the phpdocs.
Setup for scrutinizer ci.
Add poser.pugx.org composer badges.
Merge pull request #26 from nubs/scrutinizer

Add support for Scrutinizer CI
Add `url` alias to the Filterer.
Document the URL filter in the README.
Fix some typos with missing ::filter in the README.
Merge pull request #28 from nubs/add-url-to-filterer

Add url alias to filterer and document in README.
Add contribution guidelines.
Merge pull request #29 from nubs/contribution-guidelines

Add contribution guidelines.
Fix casing of "Pull Requests".
Merge pull request #30 from nubs/contribution-guidelines

Fix casing of "Pull Requests".