co-orm-macros 0.2.0

Derive macro for sqlx to implement Create, Read, Update, and Delete (CRUD) methods.
Documentation
# Derive macro for sqlx to implement Create, Read, Update, and Delete (CRUD) methods.

## Use
 adding the following to your project's Cargo.toml:
 ```toml
[dependencies]
co-orm = { virsion = "0.2", features = ["mysql"] }
sqlx = { version = "0.6", features = ["mysql","runtime-tokio-native-tls"] }
tokio = { version = "1", features = ["full"] }
 ```
 * features: mysql, postgres, sqlite, mssql

## Examples
```rust
use co_orm::{Crud, FromRow};
#[derive(Debug, Crud, FromRow)]
#[orm_rename = "users"]
pub struct User {
    #[orm_pk]
    pub id: i64,

    #[orm_by]
    #[orm_update]
    #[orm_rename = "name"]
    pub name: Option<String>,

    #[orm_ignore]
    pub add: String,
}

pub async fn get_pool() -> Result<MySqlPool> {
    MySqlPoolOptions::new()
        .max_connections(1)
        .connect("mysql://root:newpassword@192.168.1.199:3306/hello").await
}

#[tokio::test]
async fn test_query() {
    let pool=get_pool().await.unwrap();
    let u = User::get(&pool, 1).await.unwrap();
    println!("get {:?}", u);
    
}

```

``` rust
/// #[derive(Crud)]
/// generate get, get_by, query_by, update, delete, insert.
/// 
/// attributes:
/// 
/// #[orm_pk]
/// default first field is primary key or set.
/// 
/// #[orm_rename= "name"]
/// rename table name or field name.
/// default table name by struct name to_table_case: UserDetail => user_details.
/// default field name by field name to_snake_case: UserDetail => user_detail.
/// 
/// #[orm_ignore]
/// ignore field.
/// 
/// #[orm_update]
/// only update one field update_field.
/// 
/// #[orm_by]
/// generate query_by_field,update_by_field,delete_by_field.
///
/// #[derive(FromRow)]
/// impl sqlx::FromRow trait.
/// 
/// if use `#[derive(FromRow)]` macro, must use `#[derive(Crud)]` macro.
/// 
/// if you don't want to use `#[derive(co_orm::FromRow)]` macro, 
/// you can use `#[derive(sqlx::FromRow)]` macro or impl `sqlx::FromRow` trait.
/// 
/// if using sqlx::FromRow, `#[orm_ignore]` add `#[sql::defult]` .


```