CHANGED: Minor code improvements (e.g. toString() methods added).

Signed-off-by: Michael Grammling <m.grammling@external.telekom.de>
Merge branch 'channel-extensions' of https://github.com/qivicon/smarthome into channel-extensions

Conflicts:
	bundles/core/org.eclipse.smarthome.core.thing/src/main/java/org/eclipse/smarthome/core/thing/type/ChannelGroupType.java

Signed-off-by: Michael Grammling <m.grammling@external.telekom.de>
Merge branch 'channel-extensions' of https://github.com/qivicon/smarthome into channel-extensions

Conflicts:
	bundles/core/org.eclipse.smarthome.core.thing/src/main/java/org/eclipse/smarthome/core/thing/type/ChannelState.java

Signed-off-by: Michael Grammling <m.grammling@external.telekom.de>