Change force recreate tables flag to waimak configuration parameter

[alexjbush]

Description

This PR moves the force recreate tables flag in the HadoopDBConnector trait to a Waimak configuration option.

This PR also introduces the foldLeftOver on the DataFlow trait to make it easier to fold over a collection type using a DataFlow as a zero-value.

Fixes #65

Type of change

Please delete options that are not relevant.

• [ ] Bug fix (non-breaking change which fixes an issue)
• [ ] New feature (non-breaking change which adds functionality)
• [X] Breaking change (fix or feature that would cause existing functionality to not work as expected)
• [X] This change requires a documentation update

How Has This Been Tested?

Unit tests

[coveralls]

Pull Request Test Coverage Report for Build 480

• 13 of 21 (61.9%) changed or added relevant lines in 5 files are covered.
• 13 unchanged lines in 9 files lost coverage.
• Overall coverage decreased (-0.5%) to 79.529%

---

Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
waimak-core/src/main/scala/com/coxautodata/waimak/dataflow/DataFlow.scala	0	1	0.0%
waimak-impala/src/main/scala/com/coxautodata/waimak/metastore/ImpalaDBConnector.scala	1	4	25.0%
waimak-core/src/main/scala/com/coxautodata/waimak/metastore/MetastoreUtils.scala	0	4	0.0%
<!--	Total:	13	21	61.9%	-->

Files with Coverage Reduction	New Missed Lines	%
waimak-rdbm-ingestion/src/main/scala/com/coxautodata/waimak/rdbm/ingestion/SQLServerTemporalExtractor.scala	1	83.33%
waimak-storage/src/main/scala/com/coxautodata/waimak/storage/StorageActions.scala	1	93.75%
waimak-storage/src/main/scala/com/coxautodata/waimak/storage/FileStorageOps.scala	1	92.31%
waimak-core/src/main/scala/com/coxautodata/waimak/dataflow/ParallelActionScheduler.scala	1	96.55%
waimak-rdbm-ingestion/src/main/scala/com/coxautodata/waimak/rdbm/ingestion/RDBMIngestionActions.scala	1	96.15%
waimak-core/src/main/scala/com/coxautodata/waimak/dataflow/spark/SparkDataFlow.scala	2	82.26%
waimak-storage/src/main/scala/com/coxautodata/waimak/storage/AuditTableFile.scala	2	95.32%
waimak-core/src/main/scala/com/coxautodata/waimak/log/Logging.scala	2	23.08%
waimak-core/src/main/scala/com/coxautodata/waimak/dataflow/DataFlow.scala	2	93.33%
<!--	Total:	13		-->

Totals
Change from base Build 461:	-0.5%
Covered Lines:	1181
Relevant Lines:	1485

---

💛 - Coveralls