Write section about tests about development-guidelines HOT 4 OPEN

Testing frameworks. Types of testing (without writing a tutorial).

from development-guidelines.

Also, the "(TODO: Write me)" bit was meant as a bit of a joke, as tests are rarely written. We need to do something about this section though, so someone that actually knows something about testing (not me) should write it.

from development-guidelines.

Comments from Group Green.

we should use the default testing framework for each language or framework, such as unittest for python or karma for angular. In cases where a non-standard testing framework is superior, it should be noted in this document that this framework is preferred.

from development-guidelines.

Ideally, every function should have at least one test, and (where possible) functions should be kept pure (only dependent on the arguments, not on any other state) to allow for simpler testing.

from development-guidelines.