gwyddion @2.63: opportunistic use of other ports

[ryandesign (Ryan Carsten Schmidt)]

gwyddion searches for several programs and libraries that exist in MacPorts but are not declared as dependencies of the port:

:info:configure checking for update-desktop-database... no

:info:configure checking for inkscape... no
:info:configure checking for pngcrush... no

:info:configure checking for MINIZIP1... no

:info:configure checking for WEBP... no

:info:configure checking for EXR... no
:info:configure checking for h5cc... no
:info:configure checking for HDF5 libraries... no
:info:configure configure: WARNING: Unable to locate HDF5 compilation helper script 'h5cc'.
:info:configure Please specify --with-hdf5=<LOCATION> as the full path to h5cc.
:info:configure HDF5 support is being disabled (equivalent to --with-hdf5=no).
:info:configure checking for CFITSIO... no

:info:configure checking for JANSSON... no

:info:configure checking for msgfmt... no
:info:configure checking for gmsgfmt... :
:info:configure checking for xgettext... no
:info:configure checking for msgmerge... no

If the user happens to have the ports that provide any of these features installed, it looks like gwyddion will try to use them. This makes the gwyddion build non-reproducible. For each of these, gwyddion should either declare the dependency or add a configure flag to tell the build not to use it even if it is installed.