Merge pull request #28 from 52North/develop

align with current development
Merge pull request #31 from 52North/develop

merge rc.1 status to master branch
remove invalid character from pom
[maven-release-plugin] prepare release timeseries-api-rc.1
[maven-release-plugin] rollback the release of timeseries-api-rc.1
[maven-release-plugin] prepare release timeseries-api-1.0.0-rc.1
[maven-release-plugin] rollback the release of timeseries-api-1.0.0-rc.1
[maven-release-plugin] prepare release timeseries-api-1.0.0-rc.1
Merge branch 'master' of github.com:52North/timeseries-api
Merge pull request #1 from 52North/develop

Develop
Merge branch 'master' of github.com:ridoo/timeseries-api
increase version for next development cycle
fix null pointer when no label has been set
fix null pointer when no label has been set
Merge branch 'master' of github.com:ridoo/timeseries-api
update documentation
update documentation
[maven-release-plugin] prepare release timeseries-api-1.0.0-rc.2
Merge pull request #32 from ridoo/master

[maven-release-plugin] prepare release timeseries-api-1.0.0-rc.2
Merge pull request #33 from 52North/master

merge from master