Various debug updates for multiple membership levels.
Merge remote-tracking branch 'origin/dev.2' into dev.2

Conflicts:
	classes/class.pmprosequences.php
Feature: Add Sequence Settings options for sending alerts to members when new content is available.
 Added basic cron support for new content check
 Added member page links for new content
 Added new settings/options for sequence meta data.
 Added support to settings for selecting template to use for new drip content alert (per sequence).

 TODO: Missing back-end support for alert template (using the selected template). Missing back-end support for admin defined schedule for new content cron job. Want to add "Publish" metabox behavior for drop-down & edit of drop-downs.
Fix typo
Fix object reference
Comment out datediff() definition & add TODO
Fix Sequence/Series typos
Add filter to replace the introductory sentence/paragraph for the post excerpt in the alert email (!!excerpt_intro!!)
Add new formatting for sequence settings metabox, including javascript & css. Front-end only.
Admin: Sequence settings page UI upgrade with save completed. Supports 'New Content Notification' settings, including when to process and send notices.
Relocate DIV for timezone information
Validate whether to send updated content notices to users for the sequence being processed.
Add comments to source file
Start of back-end code to manage cron timing for new content notices
Back-end cron management & adding excerpt intro settings
More back-end cron work added. Still incomplete
BugFix: Would exit out of processing all sequences if one of them was configured to _not_ send notices.
Added backend processing for new content notices.
 Completed frontend new-content notice configuration with save operation (ajax and via "Post Update" button).
Started infrastructure to support per-user opt-outs of the new-content notices.
Infastructure for per-user sequence notices
Front-end for sequence specific user settings (send new content notices).
AJAX back-end framework for specific user settings (new content notices).
CSS to make new content notice opt-in box look better.