Use nimble_options for validation and docs

[coveralls]

Pull Request Test Coverage Report for Build 81dd10ac304297ec25a1059eca9160b79fc780ce-PR-245

• 24 of 25 (96.0%) changed or added relevant lines in 3 files are covered.
• 3 unchanged lines in 1 file lost coverage.
• Overall coverage increased (+0.4%) to 86.087%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
lib/redix/start_options.ex	20	21	95.24%
<!--	Total:	24	25	96.0%	-->

Files with Coverage Reduction	New Missed Lines	%
lib/redix/connector.ex	3	89.0%
<!--	Total:	3		-->

Totals
Change from base Build 13973aed04e90e4e4b5d7c08ef4af237e9a6fe1e:	0.4%
Covered Lines:	594
Relevant Lines:	690

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💛 - Coveralls