Merge branch '254-add-scaling-api' into 'develop'

...nerorchestrators/kubernetes/KServiceLifecycleManager.java

...ators/kubernetes/components/helm/HelmKServiceManager.java

...va/net/geant/nmaas/orchestration/AppLifecycleManager.java

...java/net/geant/nmaas/orchestration/AppLifecycleState.java

...geant/nmaas/orchestration/DefaultAppLifecycleManager.java

...in/java/net/geant/nmaas/orchestration/ScaleDirection.java

.../orchestration/api/AppLifecycleManagerRestController.java

...eant/nmaas/orchestration/entities/AppDeploymentState.java

...t/nmaas/orchestration/events/app/AppScaleActionEvent.java

...net/geant/nmaas/orchestration/tasks/app/AppScaleTask.java

.../geant/nmaas/portal/api/market/AppInstanceController.java

...t/nmaas/orchestration/DefaultAppLifecycleManagerTest.java

src/test/shell/data/i18n/de.json

src/test/shell/data/i18n/en.json

src/test/shell/data/i18n/fr.json

src/test/shell/data/i18n/pl.json