fixes #2599 - Bulk-selectable environments & puppet classes import

Makes the Env/Classes import a bit safer by first of all defaulting all the
checkboxes to be unchecked. Also adds multiple toggle links to selectively
realize All/New/Changed/Obsolete puppet modules.
fixes #2617 Can't edit a host once it's created
fixes #2484 and fixes #2489 - host, hostgroup, and BMC passwords are not saving