XML updates. Partial solution for bug 2187 (prob 115 now runs).
Merge branch 'master' of https://github.com/rptiwari/LaitsV3.git
Add author/instructor student graph viewing.
Merge branch 'master' of github.com:rptiwari/LaitsV3
Address bug 2187 and also made minor xml changes.
Merge branch 'master' of https://github.com/rptiwari/LaitsV3
Add Kurt's corrections to sessions documentation
Address Trello card "Add label for "root" or "base" node into all problem XMLs". Other minor aesthetic xml changes.
Added feature to save sessions from AUTHOR mode.
merge bstrong