feat/chore: Add more conversions.

[coveralls]

Pull Request Test Coverage Report for Build 5357358230

• 6 of 12 (50.0%) changed or added relevant lines in 2 files are covered.
• No unchanged relevant lines lost coverage.
• Overall coverage increased (+0.3%) to 93.13%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
imap-types/src/mailbox.rs	0	6	0.0%
<!--	Total:	6	12	50.0%	-->

Totals
Change from base Build 5320113843:	0.3%
Covered Lines:	9109
Relevant Lines:	9781

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💛 - Coveralls