merge for release candidate

version includes several features, improvements and bugfixes.

This includes 
* REST API version of specification 1.0.0 plus additional features developed since then (see [unstable/legacy section in its documeation](http://52north.github.io/timeseries-api/#nonpublic)
* more flexible parsing of documents
* easier and separate configurations of SOS instances
* upgrade of XML commons modules (now under ASL 2.0)
* overall license and quality check
* and a lot of bugfixes