Add checks to avoid NPE if not configuration defined for a device.
Merge pull request #22 from openhab/master

Merge with master
Refactoring and new features.
Commit problem fixed.
Midnight calculation bug fixed.
Fixed julian date for sun position.
Fixed julian date finally.
Fixed start of the night.
Configuration shows system timezone at startup.
Publish only changed properties to openHab.
Added sign of the zodiac.
First commit of new Wemo Binding for openHAB 1.x
Added season calculation.
Considered northern and southern hemisphere in season calculation.
Invert PercentCommand when 'invert_percent' option is true.

The 'invert_percent' option was only used in handleEvent() Method.
Use this option also for Commands sended to an ZWave Rollershutter.

Tested with Fibaro FGRM222 Roller Shutter.
Refactoring according to comments during code review and change of loglevel for discovered devices to logger.info.
add ewt temperatur as command type
Removed a FIXME from KNXCoreTypeMapperTest regarding Calimero's handling
of daylight savings time (DST) in DPT 19.001.
Added testing against multiple timezones included zones with and without
DST.
Comments revised
Merge pull request #1310 from Snickermicker/knx_dst_fixme

[KNX] FIXME removed from Testcase