Derive Hash on active enums

[kije]

Motivation

Active enums generated by the sea-orm-cli generate entity could be used as keys in hashmaps/hashsets, etc...

Thus it would be really useful if one could opt-in to having Hash automatically derived, like there is already an option for the Copy trait via the --with-copy-enums CLI option

Proposed Solutions

Add an optional --with-hash-enums option to the CLI, which then will add Hash to the traits derived on the generated active enums.

Current Workarounds

Customize generated files manually and repeat that customization after each generate.

[anshap1719]

@tyt2y3 I think it would make more sense to have an equivalent of --model-extra-derives for ActiveEnums. Do you agree? I can create a PR for that.

[tyt2y3]

Thank you @anshap1719 for the nudge.

We added --enum-extra-derives and --enum-extra-attributes recently (https://github.com/SeaQL/sea-orm/releases/tag/0.12.5), I think this issue can now be closed.