[Azoth MuC] Moved op== for AllAccounts and CurrentAccount to tests.
[Azoth MuC] Added TestDebuggable() SFINAE.
[Azoth MuC] Show typename in tests if type is not debuggable.
[Azoth MuC] Support clearing status for #1691.
[Azoth MuC] Cover clearing by tests.
[Azoth MuC] Avoid expectation failure errors on "clear.*".
[Azoth MuC] Covered last issue with testcases.
[Azoth MuC] Support accountless parsing for #1691.
[Azoth MuC] ParseChatPresenceCommand() for #1691.
[Azoth MuC] Test ParseChatPresenceCommand() for #1691.
[Azoth MuC] Use ParseChatPresenceCommand() for #1691.
[Azoth MuC] Removed unused functions.