v2.0

Mostly a maintenance release to fix error/warning messages:

• Bumps hardware.inc to v4.8.0 (thanks @tobiasvl)
• Requires RGBDS v0.6.0 or later
• Removes --disable-auto-ldh option and associated ld_long macro due to newer RGBDS version requirement
• Makes use of fstrings for a slight speed-up, so now requires Python v3.6 or later