Remove unneeded imports

[prolic]

When parsing a uuid or guid, it's required ramsey imports will be merged into the namespace imports, leading to unneeded imports in other classes of that namespace.

Solutions?

Maybe there is a way to detect unused imports right before dumping the file and thus those can be removed. Tools like php-cs-fixer can clean this up as well, but it would be much cleaner if the generated class can be kept absolutely correct.