feat: compile time checks and empty vs non empty

[dzmitry-lahoda]

• added: as subject
• NOT in this pr: adding sugar macro and method to ease creation of vec+witness and type aliases

[coveralls]

Pull Request Test Coverage Report for Build 14945025399

Details

• 36 of 62 (58.06%) changed or added relevant lines in 1 file are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-3.3%) to 47.244%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
src/bounded_vec.rs	36	62	58.06%

Files with Coverage Reduction	New Missed Lines	%
src/bounded_vec.rs	2	47.24%

Totals
Change from base Build 12837324696:	-3.3%
Covered Lines:	60
Relevant Lines:	127

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💛 - Coveralls

[dzmitry-lahoda]

@greenhat @sethdusek

please look when possible, hope sooner than later.

if you are ok - cool.

if not - will fork.

[sethdusek]

Hi, I like the approach, it seems to be the best way to have compile-time checks until generic_const_exprs is stable. Please check my review comments

[sethdusek]

Thanks!