perf(parser): Restore pre-consolidation performance

[epage]

#247 consolidated some of the parsers as suggested in #98 but there was a report of a slowdown from this change.

While this PR makes several changes, the core improvement is adding #[inline(always)] to the Parser::parse_next impls that we provide for users. I assume that created a barrier in the compiler so it couldn't optimize out the overhead from take_whiles dispatching. Somehow this only made a big difference with the ascii:: parsers and not from direct uses of take_while.

• winnow 0.4.4 for parse/hcl-edit/deeply_nested.tf: 15.235 µs
• winnow 0.4.6 for parse/hcl-edit/deeply_nested.tf: 18.273 µs
• winnow 0.4.4 for parse/hcl-edit/deeply_nested.tf: 14.513 µs

[coveralls]

Pull Request Test Coverage Report for Build 5271675064

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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• For a quick fix, rebase this PR at GitHub. Your next report should be accurate.

Details

• 15 of 15 (100.0%) changed or added relevant lines in 1 file are covered.
• 10 unchanged lines in 3 files lost coverage.
• Overall coverage increased (+0.06%) to 49.201%

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Files with Coverage Reduction	New Missed Lines	%
src/ascii/mod.rs	2	53.65%
src/stream/mod.rs	2	31.84%
src/parser.rs	6	58.49%

Totals
Change from base Build 5083769027:	0.06%
Covered Lines:	1232
Relevant Lines:	2504

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💛 - Coveralls