REST API now allows to submit credentials as part of any request

Using the custom "X-WISEBED-Authentication-Triple" HTTP header a user can submit a JSON-serialized list of authentication triples (urnPrefix, username, password), same as he would do when calling the SNAA resources login method. This saves one round trip and helps clients that don't support cookies.
Improved error message in REST API if reservation is not running and user tries to execute an operation
Fixed #335 (Node connection status does not update if TCP connection to gateway breaks)

Implemented an application level algorithms that plays ping pong with the other TCP endpoint assuming the TCP connection to be dead if the answer does not come within a certain time. Now, either host (gateway or portal) will be able to tell a small number of seconds if the TCP connection is still alive.

Includes one or two minor bugfixes (e.g. about the way channel pipelines were created) that became relevant with this feature/bugfix.
Updated dependencies
Update to WiseML-related classes, now using double precision instead of float
Updated .deb dependency list
Improved error message when gateway can't connect to a device because it is in use
First iteration of Waspmote plugin
MockDeviceAdapter flashProgram() was never ending
Fixed NPE in DeviceDBRDHelper
Fixed another NPE in DeviceDBRDHelper
Dependency management
Merge branch 'develop' of github.com:itm/testbed-runtime into feature/smartsantander
More conversion bugfixes for DeviceDBRDHelper
Merge branch 'develop' of github.com:itm/testbed-runtime into feature/smartsantander
Updated WiseGui
Fixed behavior of DeviceDBRD event broker client
Merge branch 'develop' of github.com:itm/testbed-runtime into feature/smartsantander
Tiny refactoring in DeviceDBRD
Implemented config file switch to disable scanning for iSense|TelosB|Pacemate devices on the gateway