Add pytest benchmarking extension

[EricPedley]

This lets us view the time it took to complete certain function calls. Activating the benchmarks doesn't require anything besides installing the extension and running the tests normally, and the output looks like this:

[Vince-C156]

Considering this is solely for unit testing, maybe all the requirements should be within a single requirements.txt. Also for the statistics in the screenshots you provided please add to the readme how you got these statistics and the machine you ran it on. It would be a good idea for these specs to displayed after every test. I was also not able to successfully run the test script without errors. I installed both requirements.txt and requirements-test.txt.

t depending on whos running it.

[EricPedley]

Considering this is solely for unit testing, maybe all the requirements should be within a single requirements.txt

The reason I put the normal requirements and testing tools in different requirements files is to enable us to download only the necessary dependencies when we put code on the drone. But, after explicitly stating that, I now think that we would want to run the tests on the drone anyways so I'll move them to a single file.

[EricPedley]

Also for the statistics in the screenshots you provided please add to the readme how you got these statistics and the machine you ran it on

Good point, we should be documenting exactly what systems we've got this working on. I added a line on the project root README about this.

[Vince-C156]

Failed tests not merging.