PathLayer: Wrap missing symbols
Point: Add missing properties

	* tools/extradefs/generate_extra_defs_libchamplain.cc: Add
	CHAMPLAIN_TYPE_POINT.
	* champlain/src/point.hg: Add ::color and ::size properties.
Wrap ChamplainCoordinate

	* champlain/champlainmm.h: Add champlainmm/coordinate.h.
	* champlain/champlainmm/.gitignore: Ignore coordinate.*.
	* champlain/src/coordinate.[ccg|hg]: New files.
	* champlain/src/filelist.am: Add coordinate.hg.
	* tools/extradefs/generate_extra_defs_libchamplain.cc: Add
	CHAMPLAIN_TYPE_COORDINATE.
Coordinate: Fix class documentation
Wrap ChamplainScale

	* champlain/champlainmm.h: Add champlainmm/scale.h.
	* champlain/champlainmm/.gitignore: Ignore scale.*.
	* champlain/src/champlain_signals.defs: Add ::unit and
	::max-width properties.
	* champlain/src/filelist.am: Add scale.hg.
	* champlain/src/scale.[ccg|hg]: New files.
	* tools/extradefs/generate_extra_defs_libchamplain.cc: Add
	CHAMPLAIN_TYPE_SCALE.
	* tools/m4/convert_libchamplain.m4: Add conversions for
	ChamplainUnit enum.