CMake fails to build because of order of building dependencies

[pefribeiro]

Currently, there is an embedded assumption in the generate CMake wrt convert, that can fail builds when the dependency has not finished producing the desired C++ header files. This means, in particular, that building against a Python node fails. The following needs changing:

rtcg/internal/gen/catkin/embed/templates/CMakeLists.txt.tmpl

Lines 34 to 38 in e135735

	if (NOT TARGET convert)
	add_library(convert
	../convert/convert.cpp
	)
	endif()

So that it becomes:

if (NOT TARGET convert)
    add_library(convert
        ../convert/convert.cpp
    )
    add_dependencies(convert
        TARGET_NOTE_generate_messages_cpp
    )
endif()

TARGET_NOTE needs to pull the name of the target test node. I don't think the template is called with this info, but only a bunch of dependencies. Current workaround is to change this manually for a specific example.