Update docker to build from source
fixes #476

- made statuses field on MarathonTask obsolete
- added status field that contains only the last status
- added migration for status field changes
- added `status` and `status[]` params to /v2/tasks
- updated docs
Remove incorrect `cmd` validation from frontend

The dependency of `cmd` and `container` is not defined in the backend is
now incorrect in the frontend. Rather than re-implement validation here,
defer to the backend for complex inter-field dependencies.

The `container` format changed, will also prevented scaling and
suspending from the UI. This fixes scaling/suspending in the UI for apps
using the new container format.

Fixes #496.
Merge pull request #523 from mesosphere/ui-container-cmd-validation

Remove incorrect `cmd` validation from frontend
Extracting for zip-s
Merge pull request #527 from sumkincpp/patch-1

Extraction for zip-s
Merge pull request #522 from mesosphere/wip-task-status-drexin

fixes #476
Updated migration logic for TaskTracker API change
Documentation for application groups and deployments.
Adding deployments to modal and app list
Conflicts:
	src/main/resources/assets/js/models/App.js
Slim text in buttons
Removing cmd from app list
Removing redundant code after API update
Balancing columns out
Validate executor pattern

Pattern is taken from AppDefinition.scala.
Handling errors better by showing apps list,
no matter if deployments weren't fetched
Reflect comments from ssorallen
Minor code corrections
Removing badge component
Removing update from app