Merge pull request #547 in VECTO/vecto-sim from master to develop

* commit '53b878d0':
  adding checklist for release
  new VECTO Release
  correcting testdata
  adding missing file, renaming testcase
  updating changelog
  updating lilcense number
  updating license header in new files
  adding testcase validating xml reports
  adding testcases to detect VTP cycles
  adding testcase for format of vmod and vsum files
  bugfix: correct calculation of acceleration in case simulation intervals are split up
  add condition in measured speed cycle: if the remaining interval to the next sampling point is too low, reduce the current simulation interval and thus prolong the next one
  adding testcase for xml declaration vehicle without airdrag component
  check if airdrag node exists, oterwise return null (uses standard values)