Installation instructions for FreeBSD

[pbdname]

I would like to suggest an improvement to instructions for compiling under FreeBSD (I used instructions in "INSTALL", as there are no specific instructions for FreeBSD).

The general procedure works, but one must use gmake ("devel/gmake" in FreeBSD ports tree) instead of (BSD default) make. So to build and install, one must run:

$ setenv MAKE /usr/local/bin/gmake   # in CSH / TCSH
$ export MAKE=/usr/local/bin/gmake   # in SH / BASH
$ ./config
$ gmake
$ gmake test
$ gmake install

[PeterMosmans]

Thanks for your suggestion, I'll update the INSTALL instructions (pull requests are welcome 😉).