Guile examples consistency changes

Use new guile_embedded_run target or guile_run target for running the
examples like the other target languages (for suppressing stdout if run
from top level).

Consistency with other target language file renames: use runme.scm for
scripts and example.i, example.c for example code.

Add class example to examples being tested.

Examples/guile/matrix/example.i

@@ -0,0 +1,17 @@
+/*** Matrix and vector example ***/
+
+%module Matrix
+%{
+#include <math.h>
+%}
+
+%include guilemain.i
+%include matrix.i
+%include vector.i
+
+// Include the math library so we can get some random numbers and
+// other stuff
+
+%include math.i
+
+extern double drand48();