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/constants/Makefile

@@ -2,9 +2,10 @@ SRCS   =
 TARGET = my-guile
 IFILE  = example.i
 MKDIR  = ..
+TOP        = ../..
 
 check: build
-	./my-guile -s constants.scm
+	$(MAKE) -f $(TOP)/Makefile TARGET='$(TARGET)' guile_embedded_run
 
 build:
 	$(MAKE) -f $(MKDIR)/Makefile		\