Remove "break" statemetns that break Y2R

"break" statements in the middle of "case" od "default" clauses are
impossible to translate correctly. So I added a detection of these into
Y2R (see commit e61c432579102d6b16627c6a2c8fac24ad123172 there) and
patched all known occurrences (there were just 2).

Fixes #605.