Improved JSON type and documentation system

• New annotations
• Use Java POJO classes as JSON schema descriptors
• Input parameter labeling
• More flexible validation
• Extended JSON type and documentation UIs

Module Provisioning

• New UI panels and actions for installables
• Also fixed Require-Capability headers for JSON type dependencies (- System for exporting editor slices)

Improved error handling

• Implement generic way of detecting exceptions along the stack trace (comes in handy when using lambda's and Errors wrappers).
• Make sure error messages contain useful debug information for the limeds core (function handlers)
• Specific errors should result in the correct HTTP status codes (e.g. input validation exception should result in a 400 Bad Request response)