plot bias- and trigger-patch outlines in camera

[dneise]

See title.

While plotting data for our 160 trigger patches into a camera can be simply done like

plt.factcamera(np.arange(160).repeat(9))

Its not so easy to plot some information you have for all 320 bias patches. Especially not in the light of issue #7.

So I propose to add something like:

plt.factbiaspatches(np.arange(320))
plt.facttriggerpatches(np.arange(160))

including the possibility to highlight certain patches.