Install instructions don't mention -c conda-forge

[LourensVeen]

Describe the bug
In the installation instructions, there's an instruction to install scipy and jupyter and co, which doesn't have the -c conda-forge bit, and so it fails on Anaconda installs.

[LourensVeen]

Also, the conda install pytest instruction in ./setup should add -c conda-forge --override-channels.

[LourensVeen]

While you're at it, you may want to fix You can name the environment anything you like instead of my-amuse-env. from setup as well, it should be Amuse-env for the name.

[LourensVeen]

And on the cuda installation page, there are a couple more examples that have -c conda-forge but not --override-channels.