Merge pull request #2 from VoxSupplyChain/master

cas 3 and logout flow support
fix readme format for cas3 example
Merge pull request #3 from stuartf/master

fix readme format for cas3 example
use base_url to get validate address
Merge pull request #4 from stuartf/base_url

use base_url to get validate address
allow caller to specify serviceURL
allow setting validate url
Merge branch 'serviceUrl' into cas2

Conflicts:
	index.js
Merge pull request #5 from stuartf/cas2

The CAS3 code can actually support CAS2 as well
Add info about configuring for cas2 to readme
Merge pull request #6 from stuartf/cas2readme

Add info about configuring for cas2 to readme