promotes README.md headings
Promotes headings and introduces a h3 Property Files heading for the current Local Setup Instructions
Paves way for adding additional content to README.md
switches to user.login.id as emplidUserAttribute
Credit to @jameswennmacher for identifying this improvement to defaults.
Merge pull request #15 from Jasig/use_user.login.id_as_emplid

Use user.login.id as emplid