log addition and revision

[DG12]

It would be helpful to have the log include a startup message including the version in Main
something like
LOG.info("Version: 0.2.4 begins with args:"+args+":");

Additionally, since configuration only occurs at startup perhaps using
LOG.info in config/Config.java (instead of .debug) would be helpful and not clutter logs.

For that matter LOG.info of EVERY getProperty in readConfigFromProperties
LOG.info would not only document properties but also assist in diagnosing incorrect/misspelled property names.

Thanks

[Scrin]

I don't really like the idea of logging every property, as the properties can include passwords and I don't like seeing such things in the logs.

On the other hand the misspelled property names is a valid concern as RuuviCollector has stable default values for every property so it can be difficult to spot a misspelled property. Perhaps a feature to print a warning for unknown properties would work in this case.