tests: check urbi-sending non-existing files.
tests: check urbi-sending non-existing files.

	* src/tests/examples/urbi-send.m4sh (urbi_send): New function, to
	factor.
	Check sending a file that does not exist.

urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,urbiforge/urbi,urbiforge/urbi,aldebaran/urbi,aldebaran/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi,urbiforge/urbi,aldebaran/urbi