[WIP][FEATURE] Rework workspace notification settings

Integrate a more flexible notification behaviour.

Resolves: #35245
Releases: 6.3
Change-Id: Icb680fe85fab61a51d53e3afb94b51a4930e180c
[TASK] Integrate collection selection behavior in workspace module

Since TYPO3 6.2 parent-child structures are visualized in
the workspace module. However, this representation lacks
the possibility to select all elements of that accordant
collection by one click.

A new event "holdclick" is integrated that is fired after
holding the mousedown event for 400ms. This event then
leads to have all records of the collection selected.

The regular mousedown (click) behavior still stays the same.

Resolves: #60010
Releases: 6.2, 6.3
Change-Id: I98d26f125428446157294866484f8be7106b0c51
[TASK] Simplify record icons in workspace module

The record details view renders record icons for both live and
versioned record. However, this representation is shown rather
stand-alone and can be combined with the accordant headers.

Resolves: #60015
Releases: 6.2, 6.3
Change-Id: I2f468a06271f335c491d90d825f7bcef7a9db9f6
[TASK] Possibility to disable grouping in workspace module

The workspace modules uses the ExtJS component GroupingStore
per default to group and nest version by page path. However,
this behavior get unhandy if all versions of all pages shall
be sorted by a particular column.

A new checkbox "group by path" shall be added to the top
columns menu to individually disable/enable this behavior.
Changes to that state are stored with the preferences of
a backend user for the accordant workspace.

Resolves: #60037
Releases: 6.2, 6.3
Change-Id: I8e9a2f3f14870c90ea5988a0182a54b22762390e
[BUGFIX] Workspace not always applied in RelationHandler queries

The possibly submitted value to RelationHandler::setWorkspaceId()
is not used for SQL queries to read IRRE foreign field relations.
In that case the current $BE_USER->workspace value is used which
might be different to the requested workspace id.

Resolves: #60053
Releases: 6.2, 6.3
Change-Id: Ib01e4df798ff2e1fcc8c29997f6effb814dc4344
[TASK] Refactor file references relations retrieval

The retrieval of file references in BackendUtility
is currently bound to the thumbCode() method but
is useful for other components as well.

Resolves: #60054
Releases: 6.2, 6.3
Change-Id: Id92bdeaed24d8924285a640f905ffd55db21da4d
[WIP][TASK] Missing visual representation of sys_file_reference

Resolves: #60011
Change-Id: I6d22619c264ff0e5411a47b2d566ec2c9b7c2607