Release Version 1.7.0

Enhancement: Rewrote plugin classes to bring them in sync with core files.
Upgrade: updated core files, which included some bug fixes.
Upgrade: updated WP tested version.
Bugfix: CSS fix for admin form.
Bugfix: Some option filters were being run twice.
Bugfix: Now passes the 'network_id' to get_user_count().
Bugfix: Now checking for object property in transient filter.
Minor: More work on documentation.