Add support for parsing of REF_TO keyword (defined in IEC61131-3 v3). This support is currently inactive (in flex) until we get to add C code generation later on.
syntax: glob
.project
*~
*.a
*.orig
.dep
*.Po
autom4te.cache
Makefile
Makefile.in
config.log
stamp-h1
config.status
configure
aclocal.m4
syntax: regexp
\.o$
^iec2c$
^iec2iec$
\.depend$
^stage1_2/iec_bison.cc
^stage1_2/iec_bison.h
^stage1_2/iec_flex.cc
^config/config.h
^test/