2.1.1

This release provides aggressive improvements in static introspection via
phpstan/phpstan. No functional
changes, just removed possible bugs due to excessive parameter count
in method calls, as well as test type hint fixes.

Total issues resolved: 3

• 351: Travis already has xdebug pre-installed for PHP 7.1
• 358: Fix #351 - travis has xdebug pre-installed for PHP 7.1
• 361: PHPStan inspection fixes