Generation EC can be run, several bug-fixes.

  src/data/Archive.m            - bug-fixes
  src/model/GpModel.m           - assertions about dimension of xmean
  src/model/RfModel.m           - assertions about dimension of xmean
  src/surrogate/GenerationEC.m  - bug-fixes
  src/surrogateManager.m        - mostly bug-fixes and assertions
  test/evocontrolTest.m         - new very simple test for generation EC