This commit modifies the code to no longer require a protocol version. It
does this by making use of the new Serialize function in btcwire.
Unfortuantely this does entail a public API change which I generally don't
like to do, but eliminating the usage of the protocol version throughout
the codebase was important enough to warrant the change.
To be usd for validation. Most of the codepaths teste, a few tests
missing for cases needed tests in the validation codepaths too. To be
worked on in tree.
We were counting the number of push ops instead of the number of non
push ops. Add tests that found this (checking tha the max operations
check fires).
