Merge RFC4 (#1865)

This commit is the result of the squashing of rfc4_dev branch in a single
commit. It implements mostly RFC 4 related work.

* Grid handling:
  - remove obsolete and presumably unfinished implementation of grid catalog functionality
  - all grid functionality is in grids.cpp/.hpp
  - vertical and horizontal grid shift: rework to no longer load whole grid into memory
  - remove hgrids and vgrids member from PJ structure, and store them in hgridshift/vgridshift/deformation structures
  - build systems: add optional libtiff dependency. Must be explicitly disabled if not desired
  - add support for horizontal and vertical grids in GeoTIFF, if libtiff is available
  - add GenericShiftGridSet and GenericShiftGrid classes, relying on TIFF grids, that can be used for generic purpose grid-based adjustment
  - add a +proj=xyzgridshift method to perform geocentric translation by grid. Used for French NTF to RGF93 transformation using gr3df97a.tif grid
  - deformation: add support for +grids= for GeoTIFF grids
  - horizontal grid shift: fix failures on points slightly outside a subgrid (fixes #209)

* File management:
  - add a filemanager.cpp/.hpp to deal with file related work
  - test for legacy proj_api.h fileapi
  - proj.h: add proj_context_set_fileapi() and proj_context_set_sqlite3_vfs_name() (fixes #866)
  - add capability to read resource files from the user writable directory

* Network access:
  - build systems: add optional curl dependency
  - add a curl-based default implementation for network related functionality
  - proj.h: add C API to control network functionality, and optionaly provide network callbacks
  - add data/proj.ini with default settings
  - add a SQLite3 local cache of downloaded chunks
  - add proj_is_download_needed() and proj_download_file()

* Use Win32 Unicode APIs and expect all strings to be UTF-8 (fixes #1765)
  For backward compatibility, if PROJ_LIB content is found to be not UTF-8 or
  pointing to a non existing directory, then an attempt at interpretating it
  in the ANSI page encoding is done.
  proj_context_set_search_paths() now assumes strings to be in UTF-8, and
  functions returning paths will also return values in UTF-8.

1 files changed, 12 insertions, 1 deletions

diff --git a/test/cli/testntv2 b/test/cli/testntv2
index 72a0f9a2..44ccac1e 100755
--- a/test/cli/testntv2
+++ b/test/cli/testntv2
@@ -61,11 +61,22 @@ $EXE +proj=latlong +datum=NAD83 +to +proj=latlong +ellps=clrk66 +nadgrids=ntv2_0
 EOF
 
 echo "##############################################################" >> ${OUT}
+echo "Interpolating very close (and sometimes a bit outside) to the edges a NTv2 subgrid (#209)" >> ${OUT}
+$EXE +proj=latlong +datum=NAD83 +to +proj=latlong +ellps=clrk66 +nadgrids=ntv2_0.gsb -E -d 8 >>${OUT} <<EOF
+-115.58333333 51.25000000 0
+-115.58333333 51.25000010 0
+-115.58333334 51.25000000 0
+-115.49166667 51.07500000 0
+-115.49166668 51.07500000 0
+-115.49166667 51.07499990 0
+EOF
+
+echo "##############################################################" >> ${OUT}
 echo Attempt first with ntv2_0.gsb and then conus >> ${OUT}
 $EXE +proj=longlat +datum=NAD27 +to +proj=longlat +datum=WGS84 -E -d 8 >>${OUT} <<EOF
 -111.5 45.26
 EOF
-#
+
 echo "##############################################################" >> ${OUT}
 echo "NAD27 -> NAD83: 1st through ntv2, 2nd through conus" >> ${OUT}
 #