-:PROJECT should be called first, and once.

-:SUBDIR adds an -include, expects <project>_TOP variable to be defined

Path substitution for -I statements
-:ABS_TOP sets the absolute path to the source directory
-:REL_TOP sets the relative path to the source directory
Should probably always be used as such:
	-:REL_TOP $(top_srcdir) -:ABS_TOP $(abs_top_srcdir)

Module instantiation:
-:STATIC  creates a new module that will close with BUILD_STATIC_LIBRARY
-:SHARED  creates a new module that will close with BUILD_SHARED_LIBRARY
-:EXECUTABLE creates a new module that will close with BUILD_EXECUTABLE
-:HOST_STATIC  creates a new module that will close with BUILD_HOST_STATIC_LIBRARY
-:HOST_SHARED  creates a new module that will close with BUILD_HOST_SHARED_LIBRARY
-:HOST_EXECUTABLE creates a new module that will close with BUILD_HOST_EXECUTABLE
Multiple modules can be instantiated with a single command line

Adding resources to modules (a module must be declared first!):
-:SOURCES followed by any number of source files

-:CFLAGS followed by any number of cflags
-:CPPFLAGS followed by any number of cppflags
	-Werror is silently removed!

-:LDFLAGS followed by any number of linker directives to be processed...
	-l<foo> will be added as lib<foo> to LOCAL_SHARED_LIBRARIES
	-L will be silently removed
	-pthread will be silently removed

-:LIBFILTER_STATIC followed by a list of libs (no lib prefix, or extension)
	to be interpreted as LOCAL_STATIC_LIBRARIES

-:LIBFILTER_WHOLE followed by a list of libs (no lib prefix, or extension)
	to be interpreted as LOCAL_WHOLE_STATIC_LIBRARIES

-:TAGS  must be followed by any number of: optional user eng tests

-:HEADERS followed by any number of headers for LOCAL_COPY_HEADERS

-:HEADER_TARGET sets LOCAL_COPY_HEADERS_TO
	may be followed by multiple strings, but only the last is kept

-:PASSTHROUGH followed by any number of strings to be dumped directly into
	the current module.  eg LOCAL_ARM_MODE:=arm

-:END optional... might go away in the future, was probably a dumb idea.
	ends the current module, but so does starting a new one...

