* WIP, implementing Iden
* completed implementation for DeriveIden and added basic test cases
* added feature flag to prevent sea-orm::sea-query::DeriveIden from crashing when sea-query is not used
* fixed doc test and adjusted test case
* enable `sea-query-derive`'s `sea-orm` feature
* Bump `sea-query-derive` to v0.4
* Update Cargo.toml
* Update Cargo.toml
* adjusted test cases and updated so that iden attribute will not be snake cased
* Update Cargo.toml
* Update main.rs
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Co-authored-by: Billy Chan <ccw.billy.123@gmail.com>
Co-authored-by: Chris Tsang <chris.2y3@outlook.com>
