src/avenprcore.cc,src/printwx.cc: Don't bother looking up the
printer page setup info when exporting.
src/: Pass the datestamp from the 3d file to the export code.
src/export.cc: Escape '<', '>', and '&' in labels in exported SVG
files.
src/export.cc: If the survey has a title, add it as a top-level
<title> element to exported SVG files.
src/gpx.cc: Don't try to write the title if it isn't set or is
empty.
src/img.c: Fix my_strcasecmp() to handle top-bit set characters
better.
src/: Add new "datestamp_numeric" field to struct img giving the
datestamp as a time_t in UTC (or (time_t)-1 if there's no datestamp
or we failed to convert it).  For .3d >= v8, this field is reliable.
We attempt to convert date strings in .3d <= v7 and CMAP XYZ
files, but may get the timezone wrong.
src/datain.c: Fix NULL pointer dereference when processing Compass
DAT file without 'SURVEY DATE:'.
src/: Pass the numeric datestamp to ExportFilter::header(), and use
it to set a timestamp in exported GPX files.
src/gpx.cc: Fix comment typo.
src/imgtest.c: Fix printf format to actually match types of
parameters.
tests/expobug.svx: Fix comment typo.
doc/manual.sgml: Note the station length limit Smaps used.
buildmacosx.sh,configure.ac,doc/manual.sgml: Update references to
Survex 1.1 which should be to 1.2.
src/img.c,src/mainfrm.cc: Although these are often referred to as
"CMAP .XYZ files", it seems that actually, the extension .XYZ isn't
used, rather .SHT (shot variant, produced by CMAP v16 and later),
.UNA (unadjusted) and .ADJ (adjusted) extensions are.  Since we've
long checked for .XYZ, we continue to do so in case anyone is
relying on it, but also check for the other extensions.
src/guicontrol.cc: Fix assertion if two mouse buttons are held down
at the same time.  Reported by Brian Clipstone.
src/guicontrol.cc: If dragging with more than one mouse button held
down, releasing one causes another which is still held down to take
effect.