restructures diag files, formats dates & lc's; keeps the
deployments in the metadata and starts each track at its deployment start
(metadata column deploy_start, set by smru_deployment_start()); converts
to sf geometry - all in preparation for SSM-filtering. Tracks are not
truncated at the first or last CTD profile or dive record.
smru_prep_loc(smru, meta, dropIDs = NULL, crs = NULL, QCmode = NULL)list of SMRU tables
metadata; its deploy_start column (if present) sets the start
of each track
SMRU refs to be dropped (eg. tags were turned on but not deployed)
a proj4string to re-project diag locations from longlat. Default is NULL
which results in one of 4 possible projections applied automatically, based on
the centroid of the tracks. See overview vignette for details.
specify whether QC is near real-time (nrt) or delayed-mode (dm)