feat(seq): 'seq' macro for easier skipping

[epage]

Fixes #82

[coveralls]

Pull Request Test Coverage Report for Build 5272674301

Warning: This coverage report may be inaccurate.

This pull request's base commit is no longer the HEAD commit of its target branch. This means it includes changes from outside the original pull request, including, potentially, unrelated coverage changes.

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Details

• 0 of 0 changed or added relevant lines in 0 files are covered.
• 7 unchanged lines in 2 files lost coverage.
• Overall coverage increased (+0.08%) to 49.184%

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Files with Coverage Reduction	New Missed Lines	%
src/ascii/mod.rs	2	53.65%
src/macros.rs	5	61.9%

Totals
Change from base Build 5271793117:	0.08%
Covered Lines:	1236
Relevant Lines:	2513

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💛 - Coveralls

[epage]

So I got seq!(Struct {}) working. The problem is with tuples. The only way I can find to make them work is if we do ().map which means we hit the performance problem of #237 which I was trying to avoid