Make git describe work relative to script
Make git describe work relative to script

So that you don't have to watch your CWD when running commands from the
build module.

PaulHigin/PowerShell,jsoref/PowerShell,daxian-dbw/PowerShell,daxian-dbw/PowerShell,kmosher/PowerShell,JamesWTruher/PowerShell-1,jsoref/PowerShell,KarolKaczmarek/PowerShell,JamesWTruher/PowerShell-1,KarolKaczmarek/PowerShell,TravisEz13/PowerShell,bingbing8/PowerShell,bingbing8/PowerShell,KarolKaczmarek/PowerShell,kmosher/PowerShell,daxian-dbw/PowerShell,bmanikm/PowerShell,TravisEz13/PowerShell,TravisEz13/PowerShell,TravisEz13/PowerShell,bmanikm/PowerShell,bingbing8/PowerShell,bmanikm/PowerShell,KarolKaczmarek/PowerShell,kmosher/PowerShell,KarolKaczmarek/PowerShell,jsoref/PowerShell,kmosher/PowerShell,JamesWTruher/PowerShell-1,jsoref/PowerShell,kmosher/PowerShell,bmanikm/PowerShell,PaulHigin/PowerShell,bingbing8/PowerShell,PaulHigin/PowerShell,PaulHigin/PowerShell,JamesWTruher/PowerShell-1,jsoref/PowerShell,daxian-dbw/PowerShell,bmanikm/PowerShell,bingbing8/PowerShell