Remove all unsupported layers and iteratively fix all layers

[Eirenliel]

This change adds two buttons to the Fix panel:

• Remove unsupported - removes all unsupported islands from all layers
• Fix all - performs Fix layers operation until none layers are changed, then removes all left unsupported islands and repeats and repeats until everything is fixed or nothing is fixable

Idk if it breaks the purpose of the validator, but sometimes it's really tedious fixing this by hand... The "Fix all" button takes a really long time to finish, maybe there is a need for more clarity during the process.

Implements https://github.com/Photonsters/PhotonFileValidator/issues/25

[Eirenliel]

Added invalidation of the next layer after fix and remove islands operations.

[Eirenliel]

@riggiding any reviews/suggestions? I see that you've been merging last pull requests.

[riggiding]

@eirenliel I‘m quite new to the project so I‘d like the confirmation from @bonosoft (the originator) before merging. are you on the Photonsters Facebook chat? Best to contact @x3msnake to get in

[Eirenliel]

@riggiding I'm not. Okay, I'll do it, thanks.