Added return types

[stephanvierkant]

Q	A
Branch?	3.x
Bug fix?	no
New feature?	no
BC breaks?	yes
Deprecations?	no
Fixed tickets	#1415
License	MIT
Doc

Added or changed some return types. Most of the methods already had a return type. I couldn't find any methods where a parameter type declaration could be added.

[dbu]

@stephanvierkant do you plan to follow up on the feedback? i would love to get these improvements in once we figured out the remaining questions.

[cbeyer]

Any news ?

[dbu]

i would love to get this moving again, but have little time. @cbeyer if you want to pick up the branch from stephan and do a new pull request with the conflicts resolved and possibly more strict typing cleanup, please do and i will be happy to review the changes.

[dbu]

@tacman this would be a crucial bit to modernize the code for 3.x