v0.8.0: Feature release

• [added] Support for automatic port forwarding via UPnP
• [added] Added -s shorthand for --subnet
• [added] Support for YAML config file via --config
• [added] Support for running in the background
• [added] Support for dropping permissions
• [added] Support for writing a pid file
• [added] Support for writing logs to logfile
• [changed] Not overriding recently learnt addresses in switch mode
• [changed] Caching resolved addresses to increase performance
• [changed] Configurable magic header is now used instead of Network-ID (incompatible)
• [changed] Clarified documentation on TUN netmasks
• [changed] Added timestamps to output
• [changed] Using new YAML config instead of old config files (incompatible)
• [changed] Prefer IPv4 over IPv6 when possible
• [fixed] Fixed documentation of listen parameter
• [fixed] Fixed problem with multiple subnets
• [fixed] Fixed problem with interrupted poll after suspend to ram
• [fixed] Forgot to extend peer timeout on peer exchange
• [fixed] No longer broadcasting to additional addresses