Enforce strict coverage.
Use shields.io flat svg badges.
Ignore tests for scrutinizer builds.

Tests having "invalid" stuff by scrutinizer's build typically isn't
useful.
Don't specify needless options to phpunit.
Just execute phpunit for travis.

The full build.php doesn't work for hhvm and scrutinizer helps test
everything else.
Use phpunit as a library.
Use phpcs as a library.
Remove --dev from composer install.

--dev is the default.
Merge pull request #6 from nubs/master

Update build scripts to use phpunit/phpcs as a library.