added implementation that performs a SCM update and builds only projects containing files that where changed by that update
renamed artifact to distinguish between origin implementation
modified behaviour from throwing an exception to logging an info message if no changes or updates have been detected and nothing has to be build
changed test implementation according to new behaviour
changed scm update handling strategy; decoupled from scm update and based implementation on a file containing the list of affected paths
removed java/nio/charset/StandardCharsets import to make implementation compatible to java VMs prior 1.7
removed System.lineSeparator() for compatibility reasons
changed logging from debug to info