Install dependencies from (maintained) public repos

[Jakob van Santen]

Some dependencies are currently only available from https://anaconda.org/jvansanten, which are all built by hand from the recipes in conda-recipes:

• newnuflux
• dashi

This makes it impossible to install gen2_analysis with newer versions of e.g. numpy, or on platforms other than the handful explicitly built for.

• newnuflux should be replaced with nuflux
• dashi should be either eliminated or installed from source with pip