feat(license): add license file
feat(readme): add screenshot
feat(connection layout): fix close bendpoint behavior

* Connections get properly layouted when a bendpoint is close to either of
  the connected shapes

Fixes CAM-210
Merge branch 'develop' of github.com:camunda/camunda-modeler into develop
docs(readme): update screenshot
feat(docs): Update readme
docs(readme): update license + issue tracker
docs(readme): remove contribute section
docs(readme): add contribute section
docs(contribute.md): add file
docs(readme): rename link to contribute
docs(contribute.md): rename file
feat(resize): rework resize feature

Default resize feature has two modes now
- mode 1: fix bendpoints and do not compensate shape movement (looks like
          a movement of child shapes for the user [used in participant /
	  lane right now]

- mode 2: do not fix bendpoints but compensate shape movement for children
          looks as if children have not been moved [used in subprocess]

Change participant boxing when dropped on process diagram.

Closes CAM-250
Merge branch 'develop' of github.com:camunda/camunda-modeler into develop
feat(message flow): disable create on diagram
fix(call activity): resize updates boundary pos
fix(boundary event): disable move of activities on connection
feat(product config): add product configuration

the plugins org.eclipse.core.net, org.eclipse.ui.ide.application
are not added automatically when using the resolution button
Merge branch 'develop' of github.com:camunda/camunda-modeler into develop
docs(contributing): update headings