After a long IRC discussion, it was decided that the use of direct
filepaths instead of the module is a more pure form of testing ,
although it may provide less overall coverage than the mixed integration
style imports used previously.
This will need to be remedied by further integration testing in
/test/integration.
The introduction of these two functions allow for the all the network
related code to be eventually removed from Transaction and Script.
Previously the result for non-standard transactions was undefined
behaviour. This change mandates that an exception is thrown if a
non-standard transaction is input.