[#74] Fixed subscripts that include "/" work

Fixed subscripts that included "/" as part of the subscript now work because in the trigger code, "/" in literal strings used for substitution when generating trigger code are replaced with $ZCHAR(47), which does not interfere with the "/" characters used to select options in templates when generating code. Note that a subscript of "/" in the trigger code expands to ""_$ZCHAR(47)_"" which is not pretty, but which the compiler optimizes at compile time to "/".

A test has been added in _YDBAIMTEST.m, and all tests pass.