simple_ldap 7.x-2.0-alpha2

First cut at a potential 2.0 release:

• Issue #2325505 by David_Rothstein: Account activation e-mails erroneously sent
• Issue #2328903 by emsearcy: Allow other modules to exclude roles from syncing
• Don't allow passwords to start with a NULL byte.
• Improve install-time error messages in hook_requirements().
• Pull Vagrant config from 7.x-1.x
• Handle profile form validation differently than registration validation.
• Always send notifications, always put a drupal_set_message() error notice for admins, optionally put the site into maintenance mode.
• Validate the user_profile page.
• Detect when the LDAP servers are down and optionally send notifications to a list of admins.
• Issue #2330041 by David_Rothstein: Type in error message
• ... and many many more.