Changed the dependency handling

[fschoell]

I had multiple issues with dependencies again, so I decided to fix our dependency handling. This is the PR that includes:

• Added a npm-shrinkwrap.json which saves the state of the node_modules folder and will be used by npm install instead of the package.json. This insures that we all are working with the same version of all installed packages (even of their dependencies). After an dependency upgrade, just run npm shrinkwrap to update the shrinkwrap file. In future this might be replaced by package-lock.json which is generated by the latest npm version automatically, however this still has some bugs and shrinkwrap is backward compatible to older npm versions, too.
• Changed the version handling to only update to minor versions (using ~ instead of ^)
• Updated dependencies
• Pinned the zone.js version due to a bug, see Overview of pinned dependency versions and workarounds #86

[fschoell]

@sleidig those changes are only dependency updates and refactoring, so as long as you don't get any issues with those dependencies it's fine to merge (despite of the amount of changes).

[sleidig]

Looks good to me and runs. Thanks for the cleanup.