species v0.3.1

• The spectra of AMES-Cond, AMES-Dusty, DRIFT-PHOENIX, BT-Settl, and BT-NextGen have been resampled to a spectral resolution of R=2000 and moved to a new download location (https://people.phys.ethz.ch/~ipa/tstolker/). The data size of these grids are typically several hundred MBs so downloading and processing is much faster now.
• Support for photon-counting detectors when calculating synthetic photometry. The detector type is stored as attribute with the filter profile.
• Extinction parameters have been added to FitModel: ISM extinction, a power-law size distribution of silicate grains, or a log-normal size distribution of silicate grains (see documentation for details).
• Functions in plot_mcmc for plotting the sampled extinction and size distributions: plot_extinction and plot_size_distributions.
• Refactoring of dust_util.
• Bug fix when fixing missing grid points with add_model.
• Support for the BT-Settl CIFIST spectra ('bt-settl-cifist').
• Additional unit tests and updated documentation.
• Several minor improvements, bug fixes, new features, and maintenance.