integration/monitoring: Clean up implementation

* Drop img "id" attribute
  The img id isn't used and was actually conflicting between some
  of them.

* Move "target" graphite url query to the end
  The query string can potentially be too long, in that case having
  the cut off be in the "target" will expose the problem (invalid query)
  instead of cutting off "from", which results in strange results.

* Wrap the overview graph targets in an alias() call so that
  the label is readable and fits on the page.
  (Before it was "sum(integration.,..,..)".)

* Abstract definition to be regardless of recent/longer and instead,
  in the section handling, always do both. Same result, but makes
  the code simpler and less repetative.

* Increase 'recent' fro '6h' to '24h'.

* Change graph size from 500/500 to 600/400 (more detail for recent events,
  now that it covers 24h instead of just 6h).

Change-Id: Iee468c0069d8c10d6e62c0d7ea43ca4e4dfa1ce9