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/port/Makefile

@@ -1,10 +1,10 @@
-SRCS   = port.c
+SRCS   = example.c
 TARGET = port
-IFILE  = port.i
+IFILE  = example.i
 MKDIR  = ..
 
 check: build
-	./$(TARGET) -s port.scm
+	./$(TARGET) -s runme.scm
 
 build:
 	$(MAKE) -f $(MKDIR)/Makefile		\
@@ -16,3 +16,4 @@ build:
 
 clean:
 	$(MAKE) -f $(MKDIR)/Makefile TARGET='$(TARGET)' guile_clean
+	rm -f test.out

Examples/guile/port/README

@@ -1,2 +1,2 @@
 This example illustrates the translation from Scheme file ports to
-temporary FILE streams. Read the source and run ./port -s port.scm
+temporary FILE streams. Read the source and run ./port -s runme.scm