Merge pull request #147 from rightscale/teal_13_03_acu78361_thunker_fix

acu78361 squelch thunker output if chowning TTY fails;
Merge pull request #151 from rightscale/teal_13_03_acu78361_patch_attachment_download

Teal 13 03 acu78361 patch attachment download
acu89216 implement role evolution for superuser/non login users. Refactor group/user management to be more robust.
acu89216 prototype user account locking
acu89216 disable/enable login when user loses/regains login privilege
acu89216 - Merge remote branch 'origin/teal_13_05_acu89216_role_evolution'

Conflicts:
	spec/instance/login_manager_spec.rb