idea: callable points macro also make dynamic link structure which can import from another contract

[loloicci]

It's just an idea, but

https://github.com/Finschia/cosmwasm/blob/ac1e18e57466cc86807f6bdbdbc2012d7f67632f/contracts/number/src/contract.rs#L79-L102

can make

https://github.com/Finschia/cosmwasm/blob/ac1e18e57466cc86807f6bdbdbc2012d7f67632f/contracts/call-number/src/contract.rs#L16-L22

automatically.