Added contributing

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fixed #147
added ladybug to dev requirements
moved website config of ladybug to develop
Merge pull request #151 from sulu-cmf/feature/ladybug

Fixed #147 include ladybug bundle
Merge pull request #128 from sulu-cmf/feature/contributing

Added contributing
Merge branch 'develop' of github.com:sulu-cmf/sulu-standard into develop

Conflicts:
	app/admin/AppKernel.php
	app/admin/config/routing.yml
	composer.json
	composer.lock
Merge branch 'develop' into feature/product-website

Conflicts:
	app/admin/config/routing.yml
	composer.lock