[DF-4725] Optimized UIButton load and save. Move UIControl::GetSpriteFrameworkPath to Sprite::GetPathString.
[DF-4725][DF-4764] fixed load of button states
[DF-4725][DF-4764] fixed load of button states
[DF-4725] Fix bug.
Merge remote-tracking branch 'remotes/origin/development' into DF-4725_ButtonSaveLoadOptimization

Conflicts:
	Sources/Internal/UI/UIButton.cpp
[DF-4725] Fix code after merge
Merge remote-tracking branch 'remotes/origin/development' into DF-4725_ButtonSaveLoadOptimization
[DF-4801] revert default color inherit for UIStaticText
Merge remote-tracking branch 'origin/development' into ue_stable