enhancements:
enhancements:

- wrap contraint exectuion in try-catch for proper exception ahndling
during constraint code execution
- sort the contraints first by priority descending then by name
ascending


Former-commit-id: c9abd4f4af18ee799efa72fba68119df4dffb140
webgme/webgme-engine,webgme/webgme-engine,webgme/webgme-engine