Per-feature kernel widths

[somnambWl]

• Functions for computing Gaussian and Laplacian kernels with per-feature different kernel widths
• Helper functions for orienting in BoB representation
• A bit changed names variables in functions generating SLATM, but functionality should stay the same

[andersx]

Thanks, Kuba! Can you also add an example how to use the new kernels to one of the .rst files in the docs folder, also we need a test that it runs, so we can check that it doesn't fail sometime in the future. Can you add a file in the test/ dir as well?

[somnambWl]

You are welcome :)
Sure, I will do it.

[somnambWl]

Hello, I have added one file with six new tests and a block as an example to the documentation.
I was not sure if I should run all the cells in the notebook or not, so I cleared all outputs and commited without them.
I also did not notice there was an update for the dev branch, so the last commit should be just clear merge with it.

[andersx]

Looks like the automated build fails with the pull-request! The test looks good otherwise, so I'll merge as soon as the test is fixed. Seems like a missing import in the test file.

https://travis-ci.org/qmlcode/qml/jobs/551285968

[andersx]

You can check the status of the build here: #113 (review)

[somnambWl]

It didn't find a path to directory with helper functions. I have tried to add it to init file, I hope it passes now.