Updated README
Updated README

Replaced the top-level README to narrate the project intentions and
articulate the purposes of the three sub-folders.

Unicon/cas-mfa,Unicon/cas-mfa,byu-oit-appdev/cas-mfa,bzfoster/cas-mfa,byu-oit-appdev/cas-mfa,BYU-OIT/cas-mfa,bzfoster/cas-mfa,BYU-OIT/cas-mfa,Unicon/cas-mfa,bzfoster/cas-mfa,BYU-OIT/cas-mfa,byu-oit-appdev/cas-mfa