SW-816: implemented truncate trigger which cascades a truncate on resource_claim to resource_usage and resource_usage_delta

SW-816: improved speed of the RADBCommonTestMixin by only creating a postgres instance upon setUpClass, and applying a fresh radb schema every test via setUp

SW-816: bonus feature: refactored RADBCommonTest into a RADBCommonTestMixin which takes care of setting up a testing postgres radb instance, and which can be used in conjunction with a unittest.TestCase to do unittests on a fresh RADB instance. By using a mixin instead of chained inheritance we have better seperation of responsibility, and tools like pycharm can handle these tests better as well.

SW-816: modified radb insertSpecificationAndTask into insertOrUpdateSpecificationAndTask. This has the advantage that we do not have to reconnect predecessor relations, and in the webscheduler a re-insert of a task will now be visible as an update on an existing task, instead of a delete (disappear) followed by an insert (reappear). Catch task_predecessor_unique PostgresDBQueryExecutionError in the Specification class of the resourceassigner, so scheduling can continue even on tasks which were already known and already had links to predecessors.

SW-801: bonus optimization: do loop over get_resource_claimable_capacity in database function instead of in python, thereby reducing the number of database calls dramatically.

Resolve SW-796

See merge request !26

(cherry picked from commit ae8f2617)

fe65ce37 SW-796: fixed radb tests
65b4d86f SW-796: fixed t_momqueryservice.py. We still need to un-skip IntegrationTestMoMDatabaseWrapper.
389ea3e4 SW-796: fixed tpyparameterset
4e44e3c3 SW-796: fixed t_TreeStatusEvents
63b9b189 SW-796: typos
2eb326cc SW-796: fixed ingest typos and tests
be63b190 SW-796: fixed t_qa_service
764d8d76 SW-796: fixed t_qa_service
17478140 SW-796: fixed (not-so-complete) test_ra_service_and_rpc
67306896 SW-796: fixed tRATaskSpecified
469fe393 SW-796: fixed t_resource_estimator
6d87ea88 SW-796: fixed t_schedulechecker
3fba3ba2 SW-796: fixed t_resource_availability_checker
7b1f0f7b SW-796: fixed typos in scraper.
c5dc773e SW-796: fixed t_resourceassigner
7f165dd2 SW-796: fixed t_resourceassigner
de48d55c SW-796: fixed ltastorageoverview tests: test_store, integration_test_store and test_lso_webservice
977ee079 SW-796: fixed t_schedulers
6d691753 SW-796: Merge branch 'SW-796' of git.astron.nl:ro/lofar into SW-796
ca84122f SW-796: fixed tresourcetool
98cc4a38 SW-796: fixed t_translation_service
4150a16d SW-796: fixed t_specification_service
c9a5988b SW-796: fixed t_TriggerEmailService
4e779152 SW-796: fixed t_trigger_service
60e265b9 SW-796: fixed t_trigger_cancellation_service
897bd380 SW-796: fixed build dependency for t_ingestpipeline
469e29cd SW-796: Set default port to the one in production.
2c551559 SW-795: Change timeout because its too short for the tests running on the buildhost.
47a70ce8 SW-795: Change timeout to match tested timeout

SW-801: fixed sql code to resolve bug SW-801. resource_usages arn't lost anymore when updating the start/endtimes with the same start/endtimes

SW-801: fixed test to prove root cause of SW-801. When updating a claims start/endtime to the same start/endtime, the usages are lost in the process... and that causes nasty side effects

SW-801: whoops, test did not prove bug in SW-801, but did reveil another error: as_of_timestamp was incorrect

SW-801: wrote test to prove root cause of SW-801. The returned max_resource_usage is incorrect, so the RADB and the resourceassigner draw incorrect conclusions from it

SW-801: radb should not auto_commit_selects because that would commit half-done multi-statement transactions upong doing an intermediat select. Also removed obsolete log_queries parameter.

SW-786: do not handle a PostgresDBQueryExecutionError silently in the RADB, but let the exception bubble upwards. Adapted t_radb_functionality.py tests. Should check resource_assigner and it's tests as well.

SW-786: proactively fixed UPDATE statements for postgres 10, which requires parantheses around multiple columns only. https://www.postgresql.org/docs/10/sql-update.html

SW-786: bug fix: lock the touched tables upon modification. We are forced to do this from radb.py and not in a triggerfunction in sql, because tests prove that trigger functions can recursively lock the tables causing a deadlock in a concurrent situation.

SW-786: error logging. Fix for postgres 9.6 multi-column update syntax. Minor tweak in UPDATE resource_allocation.resource_claim clauses.

SW-786: test_20190814_bugfix_SW_786 now proves there is an issue simlilar to SW-426, which is aparently (also) caused by concurrency issues

SW-786: added test test_20190814_bugfix_SW_786 to help reproduce the deadlock issue. This is the basic setup for reproduction and will serve to find the actual issue