Remove hard-coded rows and columns because this changes

[ambarb]

csxtools/csxtools/utils.py

Lines 318 to 319 in 52ff964

	flat[120:250, 0:480] = np.nan
	flat[:, 476:484] = np.nan

two options:

• pass as arguments
• look at fccd descriptors for epics plugin that reshapes the "live" image at the Beamline
• not sure this is even used, so also add deprecation warning

 logger.warning("csxtools.utils.fccd_mask() planned for deprecation. Contact beamline staff (CSX@bnl.gov) if you use this function.")

[ambarb]

on second thought, no one uses this function so we should just deprecate it along with 3D and 4D image functions because @danielballan fixed get_fastccd_images() to return the array instead of being a generator (simultaneously with tiled and dask integration #86)