Fixes related to submitr for date/time type and out-of-order references.

[dmichaels-harvard]

• Changes to structured_data support date/time types.
• Changes to structured_data support internal references in any order.
• New datetime_utils module and tests; first created for date/time support in structured_data.

[coveralls]

Pull Request Test Coverage Report for Build 7916248904

Details

• -106 of 192 (44.79%) changed or added relevant lines in 8 files are covered.
• 5 unchanged lines in 2 files lost coverage.
• Overall coverage decreased (-0.4%) to 73.775%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
dcicutils/schema_utils.py	0	1	0.0%
dcicutils/data_readers.py	2	9	22.22%
dcicutils/datetime_utils.py	46	53	86.79%
dcicutils/portal_utils.py	30	45	66.67%
dcicutils/structured_data.py	0	31	0.0%
dcicutils/captured_output.py	0	45	0.0%
<!--	Total:	86	192	44.79%	-->

Files with Coverage Reduction	New Missed Lines	%
dcicutils/portal_utils.py	1	56.9%
dcicutils/structured_data.py	4	0.0%
<!--	Total:	5		-->

Totals
Change from base Build 7787215842:	-0.4%
Covered Lines:	10130
Relevant Lines:	13731

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💛 - Coveralls