Removed no longer used query adapter.

Conflicts:
	opengever/globalindex/tests/test_task_sql_syncer.py
Dropped no longer used test-helper `task2sqltask` and use `get_sql_object` instead.
Moved TaskQuery utility in to tasks own query class: `get_task` -> `by_id`.

Conflicts:
	opengever/task/tests/test_transporter.py
Moved TaskQuery utility in to tasks own query class: `get_task_by_path` -> `by_path`.
Moved TaskQuery utility in to tasks own query class: `get_task_by_oguid` -> `by_oguid`.

Conflicts:
	opengever/task/successor.py
Task Query: renamed `by_id` to `by_intid`.
Moved TaskQuery utility in to tasks own query class: `get_tasks` -> `by_ids`.
QueryUtility: Dropped no longer used methods.
Dropped support for catalog listings in get_selected_items helper.

All tasklistings are Globalindex listings, therefore the support for catalog listings are needless.
QueryUtility: Dropped no longer used methods
Dropped no longer used ITaskQuery utility:

All queries, which are still in use, has been moved to the Task query
class (see previous commits for more information).
Dropped no longer used query method `tasks_by_ids`.