Hooks for user-defined actions

[iamdefinitelyahuman]

Overview

It should be possible to automatically perform certain tasks prior to executing specific Brownie functionality, e.g. before compiling, before running the test suite, before running a script, etc

Specification

TBD. I'm picturing a special file brownie-hooks.py in the root folder of a project. It can expect specifically named methods brownie_xxxxx that, if they exist, are called prior to certain actions. Can function similarly to pytest hooks where argument names tell which information to feed in.