Started implementation of the REST API (not yet done)

Revert "Update to new API version (see 2f87e13e78b6c2c25861c980df77f11f608ee726 in api-java)(Add optional timestamps to operation invocation messages to support scheduling in the future)"

This reverts commit 8589c2e316ff490103b207b137a60f59c9768673.
Merge branch 'develop' into feature/rest-api
Merge branch 'develop' into feature/rest-api
Merge branch 'develop' into feature/rest-api
Merge branch 'feature/rest-api' of github.com:itm/testbed-runtime into feature/rest-api
Further working on integration of REST API
Further working on integration of REST API
Further working on integration of REST API
Merge branch 'feature/rest-api' of github.com:itm/testbed-runtime into feature/rest-api
Merge branch 'feature/rest-api' of github.com:itm/testbed-runtime into feature/rest-api
Merge branch 'feature/rest-api' of github.com:itm/testbed-runtime into feature/rest-api
Further working on integration of REST API
Working on REST API
Working on REST API and WiseGui integration
REST API: switched to Jackson as JSON Provider
REST API: cleaned up a lot of stuff to have more elegant code
Working on REST API / WiseGui integration
Merge branch 'develop' into feature/rest-api
Working on integration of REST API and WiseGui
More work on integrating REST API and WiseGui