[TASK][CLEANUP] Cleanup a lot of php doc comments

Releases: 2.0.0
Change-Id: Iebd8461a3053c3dc35df331ad505f9c87355af89
[TASK] Fix several issues mentioned by scrutinizer

Releases: 2.0.0
Change-Id: I5790d86ac7936ae6f18807fc8417a892defffa4a