lazou

Results 3 issues of lazou

This PR will add support for .Net Core on the client side (for MtApi5) as requested in #134. Contract files are linked from `MtApiService` to prevent duplicated code. Only duplicated...

This PR will add [TesterDeposit](https://www.mql5.com/en/docs/common/testerdeposit) and [TesterWithdrawal](https://www.mql5.com/en/docs/common/testerwithdrawal) methods for backtesting.

Just a small improvement by enabling drag&drop of items in the inventory.