Update deps

Upgrade PHPStan to 12

Handle case where no context class exists

Refactored to single v/o

Do not replace all references

We only want to replce the reference under the cursor - the point is
that the other name is already imported so replacing them all would
break everything.

Do not try and import self/static

updates php_cs dist

bumed alias

Merge pull request phpactor#23 from dshoreman/trait-fix

Add support for traits