Merge branch 'kesapojat-master'
Update pom.xml to use correct checkstylerunner version
Updated maven deps to NB 8.0 and httpclient to 4.3.4.
Fix HttpClient deprecation warnings.
Unauthenticated error code is not 401 instead of 403.
Fix HTTP Basic auth error with 401 as the return code.

There was an NPE with the default credentials provider. Not sure why.
Upgrade cometd client lib to 3.0.0.
Set version number to 0.8.0.
Test NPE fix.
Fix PushEventListener NPE if no comet URL.