Splitting plot functions away from calculations/themis_observation.py

[lassejsc]

Added also some functionality to plot to file with outputfile and whether to draw with draw and nooverwrite. Added ncontours kwarg for phaespace_contour allowing to set the level of contours to plot and additionally via this also fixed the colorbar ticks and formatting. (Not sure why the font changes with the format but maybe someone else can fiddle with it)

Example plots given by

file="/turso/group/spacephysics/analysator/CI/analysator-test-data/vlasiator/2D/BED/bulk/bulk.0002000.vlsv"
f=pt.vlsvfile.VlsvReader(file) 
cid=1
pt.plot.themis_plot_phasespace_contour(f,cid,draw=False)
pt.plot.themis_plot_phasespace_helistyle(f,cid,draw=False)
pt.plot.themis_plot_detector(f,cid,draw=False,detector_axis=np.array([0,0,1]))

phasespace_contour

phasespace_helistyle

detector

[alhom]

Please check plotting functionality, add an example plot here and an example plotting call to the functions.

[lassejsc]

Note the change here, shading flat complained about the input shapes for this function and vmin,vmax complained about already being in the norm input, this made it plot with least amount of effort.