Make Multicorn work on BSD

[neilmcguigan]

BSD uses BSD Make, not GNU Make, and the Makefile is not compatible with BSD Make, example:

*** Parse error: Need an operator inendif(Makefile:60)

[neilmcguigan]

Here's how to compile Multicorn on OpenBSD:

Install the following packages:

• python 2.7
• gmake
• bash

Change the first line of preflight-check.sh to

#!/usr/bin/env bash

You need to use GNU make to compile it, so run:

gmake && gmake install