Account for the possibility of agents being deleted

This commit adds user's account username as one of the field to scan on quick lookup;

Conflicts:
	include/upgrader/streams/core/934b8db8-ad9d0a5f.task.php

Make selection fields play well with Advanced Search

Commit 5be0de0d introduced the idea of moving-up old saved searches to make
room for Custom Queues but failed to account for cases where the system
has more than 30 saved searches.

This commit addresses the issue by just re-inserting the old records after
queues are imported. It also adds validates & reformat the search criteria
to make the expected format.

This updates the Phone Field name back to `phone` and changes the flags
to make the variable name non-editable. This also adds a check for the
phone field on the User Form and if one exists adds it to the search.

Commit 5be0de0d introduced the idea of moving up old saved searches to make
room for custom queues - but failed to account for cases where the system
has more than 30 saved searches.

This commit addresses the issue by just re-inserting the old records after
queues are imported.

Unify ticket visibility as a routine to make sure it's applied uniformly.

Add thread entry action to create a new ticket. The entry is used to seed
ticket data like user, message (issue details) and attachments

Add thread entry action to create a new ticket. The entry is used to seed
ticket data like user, message (issue details) and attachments

Include attachments when creating a task from a thread entry

Log an internal note to parent ticket on status change
Reopen parent ticket if a closed task is reopened

Make sure that the task due date is not beyond ticket's due date.

This commit addresses a few issue in commit 131b366d

* Keep thread action triggers self contained
* Refresh the entire ticket page on successful thread action
* Fix bug where ticket id was hard coded

This adds a Ticket Thread Action for creating a Task. This action will
popup the New Task modal and will pre-fill the body of the New Task with
the body of the Thread Entry from which the action was made from.

Example:
Thread Entry - “I will need to check on the status of your account.”
Click Create Task from that Thread’s Actions
System will show New Task popup with the body as “I will need to check on
the status of your account.”

Add DateTimeField search descriptions options for supported methods

This commit addresses a few lint related issue - notable one is ignoring
undefined methods within source code comments.

Add DateTimeField search descriptions options for supported methods

Retire the need to auto-load the criteria of the last search - it's no
longer necessary since Recent Searches are now supported.

* Make saving advanced ticket search intuitive
* Make save separate operation from search (primary)
* Show inherited criteria on parent queue change

Conflicts:
	include/class.export.php
	scp/tickets.php

Add ability to select fields / columns to export for queues, including adhoc
searches.

* peter/feature/nested-kb-categories:
  FAQs Fixes
  Knowledge Base Folder Icon Positioning
  Add ability to nest Knowledgebase Categories

* aa/issue/dashboard_stats:
  Edit tool tips, add Date Range above Statistics
  dashboard statistics improvements/minor fixes