New styles for warning signs and messages. New div at the end of the #content div to house all the warnings.
Merge remote-tracking branch 'origin/master' into dev
1. Remove the testing warningSign element.
  - Now JS handles all.
2. On initialisation, JS will create all the required warning elements. Then, on highlighting the version, they will be displayed togeether.
3. Now the selected version is properly highlighted in the version dropdown.