Qx transaction limit

[Qsilver97]

Now there is a limit of 1024 SC tx per tick that makes things better but in order to handle a lot more Qx volume I think we need to have a multiple Qx command transaction. Similar to the way QUTIL does 25x normal sends to boost the throughput 25x

The Qx processing is around 25 microseconds per swap, so it seems that we can easily boost the throughput 25x by having a combined command. Maybe a vector of commands that allow for any command to be included in the 1024 extra bytes, or limit it to the same Qx transaction type.

Anyway, there is a lot of room to encode a lot more Qx transactions, especially if shortcuts are allowed to specify the token to be traded for SC shares as currently it is mostly 0s for the pubkey and issuer. Could we get it down to:
1 byte for action
1 byte (or 41 if not SC share to encode the asset/issuer or just SC index)
8 bytes for price
8 bytes for amount

Seems that up to 60 QX commands can be squeezed into a single tx!
Even the tokens can get around 15