Pyjams

* Write standard output file of mcPlot into current folder.
* Add `str2tex`, converting strings to LaTeX strings
* Bug in masked array input to `alpha_equ_h2o`, needed to check masked array
before ndarray because the former is also the latter.
* Enhanced tests of `alpha_equ_h2o`, `alpha_kin_h2o`, `fit_functions`,
`argsort` so that have 100% coverage.
* Added `color`, a collection of color palettes and continuous color maps.

* Add `mcPlot`, the standard plotting class of Matthias Cuntz.
- It currently assumes that MyriadPro is installed for LaTeX if one
wants to typeset with latex (-u, --usetex). For installing MyriadPro
on macOS see https://github.com/mcuntz/setup_mac#myriad-pro This
should be similar on Linux.
- There are no tests for mcPlot yet.

* Avoid overflow warnings in `alpha_equ_h2o`.
* Added `alpha_kin_h2o`, kinetic fractionation factors for molecular
diffusion of water isotopologues.

* Added `alpha_equ_h2o`, isotopic fractionation between liquid water and
vapour.
* Added `pyjams` to conda-forge.

* Added `division`, divides arrays dealing with zero in denominator.

* Added `argmax`, `argmin` and `argsort` for array_like and Python
iterables.