chore(cockpit tests): add angular specific test helpers

Related to CAM-802
feat(cockpit plugins): add client side view service

Plugins must register agains the ViewsProvider now.

A pluggable view may be defined via
`<view vars="vars" provider="provider"></view>`.

Closes CAM-801
Merge branch 'master' of github.com:camunda/camunda-bpm-platform