Extract Decred-specific mempool policy

[davecgh]

Pull request #263 syncs in the upstream mempool policy structure however it does not add the new Decred-specific variables to it. That must be done before the mempool can properly be split out into a separate package.

Also, the code in rpcserver.go is improperly referencing the mempool policy from the block template generation code, so the variable for maxSigOpsPerTx had to be added to it in order to keep the code working. The comment added as part of the PR explains why:

    // NOTE: This is being added while syncing upstream because the code in
    // the RPC server here is referencing the variable even though it most
    // definitely shouldn't be.  It is a policy limit regarding what should
    // be relayed or mined and thus should only apply in the mempool and/or
    // possibly the mining code.

[MiguelMoll]

Is this issue still valid given #496 refactored mempool into it's own package?

I see rpcserver.go is still referencing maxSigOpsPerTx .

Trying to find something "simple" I can help with. 😉

[davecgh]

Sorry for the late response. This one slipped by me somehow. It still applies.

[davecgh]

As it turns out, you are correct that it no longer applies. I was thinking about the priority code which is handled by PR #1110.