adg: added (transfer none) to AdgPath
cpml: protect CpmlPair methods against NULL args
cpml: protected CpmlPrimitive APIs against NULL args
cpml: return if a point exist in CpmlPrimitive

Return a flag from cpml_primitive_{set,put}_point() indicating if the
point is found.
cpml: removed CpmlPath

CpmlPath was an alias for cairo_path_t: modified the code to directly
use cairo_path_t and removed cpml_path related APIs.
adg: refactored _adg_read_cairo_path()
doc: added missing adg-rdim.c to POTFILES.in
test: updated test units
adg: properly initialize all AdgPath fields
adg: annotation bug in adg_path_append_array
adg: fixed remapping of AdgPath over primitive

When an element is added to a GArray, the data can grow and be remapped
to another place. Corrected a long-standing bug that did not take into
account this remapping.