Log Message:
devel/rgbds: add version 0.3.7

RGBDS (Rednex Game Boy Development System) is a free assembler/linker
package for the Game Boy and Game Boy Color. It consists of:

* rgbasm (an assembler)
* rgblink (a linker)
* rgbfix (a checksum/header fixer)
* rgbgfx (a PNG-to-Game Boy graphics converter)

This is a fork of the original RGBDS which aims to make the programs
more like other UNIX tools.