Merge pull request #11 from Jerome-github/rfm2pigateway_dev

RFM2Pi Gateway port to emonCMS dev branch
Fix missing rememberme class in raspberrypi_run
RFM2Pi Gateway: make script daemonizable

- Remove PID management, will be done by caller init script
- Opt-in logging: default logging goes to STDERR,
  optional --logfile parameter allows to pass a file path
- Retry to get settings every 10 sec (in case apache or MySQL
  is not started yet)
RFM2Pi Gateway: Daemonize RFM2Pi Gateway

See readme.md for installation/usage instructions
RFM2Pi Gateway: start/stop, read logs from web GUI