in the stats2 method; removed the merge operation and moved the mask_match operation prior to outlier removal; in the mask_match method, added optional input with error message content; implemented ismaskcommon method; corrected comments in merge and interp2
in the stats2 method; removed the merge operation and moved the mask_match operation prior to outlier removal; in the mask_match method, added optional input with error message content; implemented ismaskcommon method; corrected comments in merge and interp2

jgte/orb,jgte/orb,jgte/orb,jgte/orb,jgte/orb