Unexpected file name on writing the solution

When calling `model.write('myfile.mps')`, the resulting output file `myfile.mps.mps.gz` is created.

1. Please remove the invalid `mps.mps` suffix, the end result should be named `myfile.mps.gz`.
2. It would likely be better if I were given an API option to choose if I want the result zipped or not. In my case, plaintext would be much better since I want to store this in a source control repository as a regression test, so now I have to add a step to unzip the file inside my process.

Thank you.

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Running python 3.7 on mip-1.13.0 on both Windows and Linux.