Release notes 2.0.1 EA

This is a tiny patch release that fixes platform compatibility (mainly macOS) and compatibility with latest GameMaker runtimes.

Fixed errors caused by treating variable id as a number. This for example caused PushEd to crash when selecting an instance.
Added new functions PEd_ShowQuestionAsync and PEd_ProcessQuestionCallbacks to replace show_question, which does not work on all platforms.
Replaced function PEd_GetFloat with PEd_GetFloatAsync, as the synchronous version did not work on all platforms.
Updated style of documentation comments for better compatibility with Feather.