changes of the HTML comment sections used by grunt

Reorganized of the comment sections used by the grunt build target in
index.html
updated display mechanisms for concepts

- now one map layer is used per concept
- now all given concepts are displayed on the map if a Sponate mapping
  is given
- now the map update is not triggered by the save button anymore, but
  via the 'update map' button
- the map update can only be triggered if the initial and maximal map
  section is defined