work towards CCGMS compatibility

c64/basic/ad9e.frmevl.s

@@ -0,0 +1,5 @@
+
+// XXX provide documentation and implementation
+
+FRMEVL:
+	STUB_IMPLEMENTATION()

c64/basic/ad9e.interop

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+
+This routine is desribed in Mapping the C64, page 102, and used at least by CCGMS terminal software - see here:
+- https://raw.githubusercontent.com/spathiwa/ccgmsterm/master/original/5a.gs

c64/kernal/assets/e8da.interop

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+
+A color code table, see here:
+- https://csdb.dk/forums/index.php?roomid=7&topicid=487
+
+CCGMS termina program expects it to be under original location, see here:
+- https://raw.githubusercontent.com/spathiwa/ccgmsterm/master/original/5a.gs