Add simulation tests for both `mg-nft` and `mg-market` contracts

[acuarica]

Simulation tests allow us to test cross-contract calls locally. To do so, it deploys contracts locally usingnearcore.

You can read more about simulation tests here:

https://github.com/near/near-sdk-rs/tree/master/near-sdk-sim

• Tasks

• [x] Add near simulator rust project

• [x] Add tests cases in simulator

[acuarica]

Introduced in #80.