This patch addresses two problems in the install scripts:

1) If a rule with syntax error is encountered, the UDF will return the
string "Loading of some rule(s) failed.". The SP doing the load would
then do SIGNAL, without clearing the query cache. Hence queries which
now match rules are still cached, causing them not to be
rewritten. Fixed by clearing the cache before signalling.

2) The ID column was not added in all four variants of the install
scripts. It is now.