Proposal: Add method for mapping

[pyAndr3w]

At the moment, to remove an element from mapping, we can only use

delete mapping[key]

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However, in TVM there is an opcode for simultaneous deletion and retrieval of an element - DICTDELGET.

It would be very convenient to use this method to save on gas.

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expected syntax:

<map>.getDel(KeyType key) returns (optional(ValueType));

[cryshado]

@pyAndr3w Hi, thank you for the issue! We plan to implement this in the next version

[cryshado]

Implemented in 0.71.0 (2023-07-20) #141