PROCEDURE: fit_pad_mag PURPOSE: Determines the time offset between MAG1 data and SWEA MAG angles. For SWEA pitch angle sorting, the magnetic field is averaged over the second half of the 2-sec measurement cycle. However, there can be apparent differences between the MAG and SWEA timing if one of the decommutators has an error. Here, I assume that the SWEA timing is correct (naturally) and fit for a constant MAG time offset. USAGE: fit_pad_mag INPUTS: KEYWORDS: RESULT: Timing and angular offsets. The timing offset is robust. Angular offsets are for reference only. $LastChangedBy: dmitchell $ $LastChangedDate: 2014-10-31 14:15:03 -0700 (Fri, 31 Oct 2014) $ $LastChangedRevision: 16106 $ $URL: svn+ssh://thmsvn@ambrosia.ssl.berkeley.edu/repos/spdsoft/trunk/projects/maven/swea/fit_pad_mag.pro $ CREATED BY: David L. Mitchell 07-24-12