rgbds 0.1.0 (new formula)

Game Boy assembler and linker. I do a custom install because the makefile does funky stuff with the man path that causes 'make install' to fail.

https://github.com/bentley/rgbds
The make install fails with issue relating to copying man files. I tried to use "MANPREFIX=#{man}" and it fails with the following:

    ==> make install MANPREFIX=/usr/local/Cellar/rgbds/0.1.0/share/man
    install: /usr/local/Cellar/rgbds/0.1.0/share/man/man7/rgbds.7: No such file or directory
    Installing manpages to /usr/local/Cellar/rgbds/0.1.0/share/man failed.