Added M_INFO field

[rosen4o]

According to version 5.0 of the documentation from 12 Aug 2024 M_INFO field is required for transactions with VISA cards

[veneliniliev]

Thank you for the PR.

• According to the documentation, the data should be in this format: {"email":"[email protected]","cardholderName":"CARDHOLDER NAME","mobilePhone":{"cc":"359","subscriber":"8939999888"}}. At least this is how the example is given. You've mentioned it incorrectly in README.md.
• Will there be any issues if this field is not filled in with the current version?
• The tests are failing and we will need to update them to accommodate this parameter.

We need to resolve these issues before we can merge the PR.

[rosen4o]

Have added backward compability and updated information in the README file

[veneliniliev]

@rosen4o Thank you for the PR. It has been merged.