fix(webapps/css): responsive tweaks

- make breadcrumbs responsive
- make footer responsive
docs(webapps/uri): add docs to uri directive
chore(webapps/debouncer): rename debounce directive
impr(webapps/authentication): rework client side auth + setup

- add directives if-logged-in and if-logged-out to conditionally render
  content
- rewrite Authentication service
- rewrite ProcessEnginesFilter
- explicitly add <base href="" /> to app main files

Related to CAM-1021
feat(webapps/tasklist): merge tasklist into main webapp

Related to CAM-1021
docs(README): rename dojo packaging readme
chore(distro): remove tasklist from distro + fix it

- tasklist (now part of camunda-webapp) removed from distro
- tasklist integration test fixed

Closes CAM-1021
chore(cleanup): remove old tasklist files

Related to CAM-1021
chore(webapps): remove old cockpit config file
chore(merge): merge into master
feat(authorization): identify administrative user by camunda-admin group

Administrative users for camunda BPM must be members of the group
`camunda-admin` (Groups.CAMUNDA_ADMIN). The camunda web
applications will check, whether a user in such a group exists and if
not will ask the user to create such an administrative user.

- update test data and setup resources accordingly

BREAKING CHANGE

Administrative users are now identified by membership in group
`camunda-admin`. Add a user with that group to a process engine
if you would like to prevent the initial setup dialog.

Closes to CAM-1029
fix(examples): create users in invoice example

Create demo users required to walk through the invoice example during
bootstrap of the application.

- add application landing page that points to valid users
- add link from camunda-welcome to example

Closes CAM-1030
Merge branch 'master' of github.com:camunda/camunda-bpm-platform