More Flashforge G-code commands

[KeltE]

Perhaps it is useful. Here also for some flashforge printers Fan mod and temp. firmware. https://github.com/moonglow/flashforge_fan_fix

Code	Comment
~M504	Reset filament usage counter ( use with login )
~M601 S1	Login command
~M602	Logout command
~M611 Sn	Set tool count, can be 1 or 2
~M615	Reset printer usage counter ( use without login )