feat: add more Content-Formats

[JKRhb]

This PR adds a number of missing Content-Formats as a default and makes it possible to use Content-Formats with parameters. It also updates the README with a table of the supported Content-Formats instead of a JavaScript source code listing.

There might be an issue that arises from the fact that the space between Media-Type and parameters is optional but I would deal with that in another PR.

[coveralls]

Pull Request Test Coverage Report for Build 1282300270

• 5 of 5 (100.0%) changed or added relevant lines in 1 file are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage decreased (-0.1%) to 89.697%

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Totals
Change from base Build 1280604248:	-0.1%
Covered Lines:	1067
Relevant Lines:	1158

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💛 - Coveralls

[coveralls]

Pull Request Test Coverage Report for Build 1282257649

• 5 of 5 (100.0%) changed or added relevant lines in 1 file are covered.
• 2 unchanged lines in 1 file lost coverage.
• Overall coverage decreased (-0.2%) to 89.581%

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Files with Coverage Reduction	New Missed Lines	%
lib/cache.js	2	94.74%

Totals
Change from base Build 1280604248:	-0.2%
Covered Lines:	1065
Relevant Lines:	1158

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💛 - Coveralls