Contents updated for Sisimai::Bite

[azumakuniyuki]

• Sisimai::MTA, Sisimai::MSP have been moved to Sisimai::Bite::Email
• Sisimai::CED has been moved to Sisimai::Bite::JSON
• set-of-emails/jsonapi has been renamed to jsonobj
• File prefix of the almost emails samples have been changed: mta- => email-

[azumakuniyuki]

Merge after the release of Sisimai 4.22.0