multiplex-funnel: support more than just Q_TABLE results
multiplex-funnel: support more than just Q_TABLE results

Add support for Q_TRANS, Q_UPDATE and Q_SCHEMA query types.  No support
is implemented for Q_PREPARE (would require globally consistent exec ids
so near to impossible).

One can now perform create, insert, update, delete and select statements
over a multiplex funnel getting single answers to all queries (though
seeing weird results for update queries in their simplest form of
course).  Transaction support was added because it is very simple,
however, I doubt if it really a good idea to use it with a cluster.

zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb,zyzyis/monetdb