(PE-2410) lift 'add-classpath' out of pomegranate

https://github.com/cemerick/pomegranate
(PE-2410) additional docs for 'add-classpath'
(PE-2410) improve comments about classpath stuff
Merge pull request #26 from KevinCorcoran/add-add-classpath

(PE-2410) lift 'add-classpath' out of pomegranate