The name of an alignment calibration file. The alignment file specifies
a rotation and a roll angle convention using the ALIGNM, ROLLSIGN and ROLLOFF
keywords from the teldef file. The rotation will be applied to the attitude before
it is reported and the roll angle will be expressed using the given convention.
For example if a teldef file is used for alignfile, the R.A. and Dec. values
will correspond to the instrument pointing, not the spacecraft Z axis pointing.
If the file name is set to "none" (case insensitive), then the default alignment
will be used. The default alignment has no rotation and uses the default roll
angle convention.