Resolves Issue #30

Changed to use a more BASH friendly method where it solely
relies on PWD and cd to ascertain the correct path
Works on OSX.
Merge pull request #36 from admackin/master

Fixes #32 - write the die() function to the generated run script, and also adds a few comments to the docs
Merge pull request #34 from rbuckland/master

Fix #30 Uses a script detection that works on OSX as well as Linux