Clear MQTT Connection watchdog on error
Fix HTTTP Request url template
Bump 0.7.1
Tidy up REST interface

 - Ensure application/json where appropriate
 - Use jquery api rather than d3
Fix library ui
Fix MQTT client reconnect logic
MQTT Client - missing null check
Handle port-in-use error on start-up
Add version information to log output
/nodes end-point should be text/html not json
Tidy up ajax usage
Add ws heartbeat to keep connection alive through firewall
Bump 0.7.2
Import unknown config node breaks layout
Fixes #211
Functional Fix for Inject node
addresses Issue #209
Interval is now wholly timeout based.
Now works on Sundays
Add parser function nodes for XML, JSON and CSV.
Each is dual function - pass in (for example) and get out a js object, pass in a js object and get back out the xml string.
The CSV node must be configured with a column template that specifys the required property names for that column (csv->js), or the properties of the object that should be made into the csv (js->csv)
Merge pull request #207 from fvdpol/master

Add configuration of serial protocol settings (25-serial node)
Tweak layout of serial port config (Thanks Frank)
Generate content-length on HTTP Request node
Add File In node