feat: add all missing APIs for all objects: group, model, adapter, enforcer, etc.

[hsluoyz]

Similar to: https://github.com/casdoor/casdoor-go-sdk/issues/76

Some operations for cert is missing, and:

• group
• model
• adapter
• enforcer

And:

• product
• payment
• plan
• pricing
• subscription

And:

• syncer
• webhook
• sysinfo

[casbin-bot]

@seriouszyx @ComradeProgrammer @Resulte

[hsluoyz]

@leoil