Extend imports for new types/kinds

[oubiwann]

Tasks:

• [ ] Change import --type to --format
• [ ] Add support for --type (kind)
• [ ] Add JSON deserialisation capability
• [ ] Add json to the allowed types for import
• [ ] If the --type for import is Kind::AsymmetricCrypto, Kind::Certificates, or Kind::ServiceCredentials, set the format to JSON
• [ ] If no type is set, check the file extension
• [ ] When exporting to JSON, support limiting by --category
• [ ] When exporting to JSON, support limiting by --tags

Depends on:

• 71