Merge branch 'pac4j-3.x' into 'master'

Migrate Pac4j to version 3.4

See merge request !111
6 jobs from master in 1 minute and 47 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Build
failed #96735
maven allowed to fail
checkstyle

00:00:22

passed #96736
maven
compile

00:00:32

 
  Post Build
passed #96738
maven
package

00:00:25

passed #96737
maven
unit_test

00:00:31

 
  Deploy
passed #96740
maven allowed to fail
sonarqube

00:00:44

manual #96739
python allowed to fail manual
tomcat_development
 
Name Stage Failure
failed
checkstyle Build
[INFO] ------------------------------------------------------------------------
[ERROR] Failed to execute goal org.apache.maven.plugins:maven-checkstyle-plugin:3.0.0:check (default-cli) on project arsnova-backend: You have 633 Checkstyle violations. -> [Help 1]
[ERROR]
[ERROR] To see the full stack trace of the errors, re-run Maven with the -e switch.
[ERROR] Re-run Maven using the -X switch to enable full debug logging.
[ERROR]
[ERROR] For more information about the errors and possible solutions, please read the following articles:
[ERROR] [Help 1] http://cwiki.apache.org/confluence/display/MAVEN/MojoFailureException
ERROR: Job failed: exit code 1