CI: Create staging area

This commit setups CI for protected branch staging. It
should contain changes that are to be merged into master.
10 jobs from staging in 10 minutes and 51 seconds (queued for 2 seconds)
Status Job ID Name Coverage
  Prepare
passed #190845
prepare:activemqcpp

00:00:28

 
  Build
passed #190847
build:webui

00:03:18

passed #190846
build:worker

00:00:43

 
  Test
passed #190849
test:webui

00:01:01

passed #190848
test:worker

00:00:21

 
  Deploy
passed #190851
deploy:client:staging

00:05:35

passed #190850
deploy:server:staging

00:02:10

passed #190852
deploy:worker:staging

00:01:54

 
  Notify
passed #190861
notify:altvm

00:00:28

passed #190853
notify:altvm

00:00:14