Listen to error events from Structs while parsing
Make a wrapper function to remove boilerplate from wrapping functions
Struct doesn't really have to be an event emitter

We're not using a callback, so can't return early on a failure, so just set an internal state property instead.
WrapStruct method not needed with simplified Struct process.
Event name doesn't have to change when bubbling
Add more tests for valid message structures
Update documentation
Merge branch 'parsing-handling'

Conflicts:
	lib/BTCNetwork.js