pc_align: Bug fix for out-of-mem condition
pc_align: Handle properly no-data pixels
pc_align: Print lat-lon-height translation vector
pc_align: If both inputs are DEMs, do some logic by intersecting the boxes to filter
pc_align: Add percentile stats, as well as mean and stddev. Document
pc_align: Fix comment
stereo_tri: Bug fix for PC center calc
parallel_stereo: Rm hard-coded file list assumptions, etc.
point2dem: Eliminate erosion when subsampling with --fsaa
stereo_pprc: Skip image normalization in special circumstances
sparse_disp.in: double the dilate radius

We were dilating the quality mask by coarse_skip/2.  This leaves gaps, which should go away if we double the kernel width.
sparse_disp: add debugging options, catch bad-match errors

-Can now specify -D to get an output csv of disparity points, a second csv of points that have failed with an indication of why they failed, plus chit-chat from the script as it runs

-Errors where norm_xcorr returned 'None' were getting passed through as zero-disparity points.  These should have been deleted.
sparse_disp: change success criteria

1. increase teh default epipolar tolerance
2. allow the minimum maximum-disparity value  to be specified