Workaround for player in PE
Workaround for player in PE

It looks like multi-player game non local players aren't cached in MCEdit.
This caused a crash when trying to access these players cached data.

Also added a message when using `--debug-pe` CLI switch.

Khroki/MCEdit-Unified,Khroki/MCEdit-Unified,fhfuih/MCEdit-Unified,fhfuih/MCEdit-Unified,Khroki/MCEdit-Unified,fhfuih/MCEdit-Unified