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
updated dependencies
updated config to new error handling
Merge pull request #160 from sulu-cmf/enhancement/error-handling

[ENHANCEMENT] updated config to new error handling
Refactored kernel structure
Fixed travis
Updated
Removed parameters.yml
Added PHPDoc
Added context to container:
Updated README for new file structure
Fixed composer.json
Configured corrcet log directory
Do not include uncessary bundles in uncessary contexts