merge changes from eam_branches/ipp-20140423: add dcr-color option, ref_color, bad detection clipping to relastro; fix RA,DEC for mosaics in imextract; allow photdbc to restrict images to output region; change PHOTCODE_SKIP_LIST to PHOTCODE_KEEP_LIST in photdbc; add -reset-to-photcode option to relastro; ensure relastro child processes get the complete set of options; allow relastro region hosts to continue after load-object clients are done, but before the data is loaded; invalidate extreme proper motion; limit relastro catalog density on a grid; require more detections for higher order fits; option to delete duplicate images based on exp time/date and photcode; have kapa use XSync instead of XFlush to avoid flashing; handle some cases to avoid crashing kapa; extend kapa connection timeout; allow kapa to handle > 2GB images; ensure dvomerge works even if incoming db has no images; add dvo fuctions coordmosaic & psastro_model
