Fix colors and labels in xml2png

[choderalab]

Fix colors and labels in xml2png

[jchodera]

These scripts now use seaborn as of: 89af934

I don't know enough about pandas to figure out how to fix the labeling of the plots, but we would hopefully also allow these plotting scripts to be flexible enough to use either 96- or 384-well plates.

[sonyahanson]

That should be read as 'seaborn so colors are more informative', for example as a consistent rainbow starting with A as red, so it is easier to see what is going on at a glance.

Also, I think xml2png.py should already work for 96 or 384 well plates, at least in the latest iteration I was using. I think we just plotting a pandas dataframe assuming a 384 well plate, and if the rest were 0's if it was a 96 well plate, and it still worked fine. This is pretty slap-dash, though.

[sonyahanson]

Fixing colors and labels pull request fixes this.