v0.7.0

Updates v0.6.0...v0.7.0:

• json logging (-json), and custom loglevel (-loglevel): #175 (@metachris)
• registerValidator: remove signature check, leave up for relay: #176 (@metachris)
• Simplify OK responses across handlers: #171 (@0xpanoramix)
• improved error and ok response (with error handling): #177 (@metachris)
• Add relays statuses calls in boost status endpoint: #172 (@0xpanoramix)

Updated images are available on Docker Hub: https://hub.docker.com/r/flashbots/mev-boost/tags