Create batch versions of multiple evaluation functions

[jeremykubica]

Closes #192

Allow a GraphState with multiple samples to be passed to PhysicalModel.evaluate() and PhysicalModel.get_band_fluxes(). In the process update Passband.fluxes_to_bandflux() so that it can also process a batch of samples at once.

[github-actions]

Before [817d06f]	After [c34d845]	Ratio	Benchmark (Parameter)
711±500μs	1.43±0.8ms	~2.01	benchmarks.TimeSuite.time_fnu_to_flam
4.44±0.4ms	6.32±0.8ms	~1.42	benchmarks.TimeSuite.time_chained_evaluate
8.43±0.4ms	10.3±0.4ms	1.22	benchmarks.TimeSuite.time_evaluate_salt3_model
4.59±0.09ms	4.99±0.08ms	1.09	benchmarks.TimeSuite.time_evaluate_salt3_passbands
1.36±0.06ms	1.46±0.05ms	1.07	benchmarks.TimeSuite.time_apply_passbands
27.1±0.4μs	27.6±0.4μs	1.02	benchmarks.TimeSuite.time_make_new_salt3_model
8.85±0.05ms	8.94±0.1ms	1.01	benchmarks.TimeSuite.time_load_passbands
1.34±0.01s	1.35±0.01s	1.01	benchmarks.TimeSuite.time_make_x1_from_hostmass
122±1μs	124±1μs	1.01	benchmarks.TimeSuite.time_sample_x0_from_distmod
16.1±0.3μs	16.2±0.2μs	1.01	benchmarks.TimeSuite.time_sample_x1_from_hostmass

Click here to view all benchmarks.

[OliviaLynn]

Looks good!