Problem: markdown docs have no code highlighting for interfaces/tests
Problem: markdown docs have no code highlighting for interfaces/tests

Solution: add a markdown fence to enable code highlighting in markdown.

paddor/zproject,paddor/zproject,zeromq/zproject,twhittock/zproject,eburkitt/zproject,taotetek/zproject,paddor/zproject,taotetek/zproject,eburkitt/zproject,zeromq/zproject,twhittock/zproject,zeromq/zproject,taotetek/zproject