Add library tests as unit tests

[StefanJum]

Use the library tests. Use uktest, Unikraft's unit testing framework. Check the implementation of testing for libsodium as a model.
The mimaloc library has its own testing api and helper symbols, try to patch it to use uktest.

Hackathon points: 80

[hchandad]

Picking this one up, still on the first steps of building and running it, i am keeping notes in this hackmd page, updating as i go.

[hchandad]

Pull request #3