Manage Groups - Pager and Search

Rationale
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Large and distributed organizations will have a large number of groups for segmenting their contacts into chapters/regions and for permissioning. The current Manage Groups interface puts all groups on a single page, and there is not mechanism to search for a group or filter group listings.

Implementation
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1. Add our standard Pager to the Manage Groups selector. Behaviors are the same as for contact selector - using the Group Title as the handle for alpha filtering.

• AtoZPager element is always included. Letters are linked to filter action when one or more group title(s) start with that letter.
• Go to page / next-previous .... element is included when number of returned rows is greater than "rows per page" value.

2. Add a simple search form above the selector. Search is on Group Title and/or Type and/or Visibility.
NOTE: See issue CRM-2263 which adds support for assigning "types" to groups (e.g. Mailing List, Access Control Group).

Search fields (place side-by-side to minimize horizontal space)
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Label = "Find", Type = Text
Desc = Full or partial Group name.

Label = "Type", Type = Checkbox
Option values = select from civicrm_option_value where option_group.name = group_type

Label = Visibility, Type = Checkbox
Option values = 'User and User Admin Only', 'Public User Pages', 'Public User Pages and Listings'

NOTE: I think we should use LIKE '$titlestring%' in the search query