ibis_etc: need Gaia g-band color terms!

[dstndstn]

Traceback (most recent call last):
  File "/home/declsp/decam-guider/ibis_etc.py", line 2884, in <module>
    etc.run()
  File "/home/declsp/decam-guider/obsbot/obsbot.py", line 541, in run
    gotone = self.run_one()
  File "/home/declsp/decam-guider/obsbot/obsbot.py", line 515, in run_one
    self.process_file(fn)
  File "/home/declsp/decam-guider/ibis_etc.py", line 2777, in process_file
    self.start_exposure(path, expnum)
  File "/home/declsp/decam-guider/ibis_etc.py", line 2749, in start_exposure
    etc.process_guider_acq_image(path, self.roi_settings)
  File "/home/declsp/decam-guider/ibis_etc.py", line 295, in process_guider_acq_image
    R = meas.run(**kw)
  File "/home/declsp/decam-guider/obsbot/measure_raw.py", line 529, in run
    colorterm = self.get_color_term(stars, band)
  File "/home/declsp/decam-guider/ibis_etc.py", line 1465, in get_color_term
    coeffs = polys[band]
KeyError: 'g'