GitLab

- moving the following classes over from OPAL to CLASSIC
  o OpalField       -> ClassicField
  o OpalRing        -> Ring
  o OpalRingSection -> RingSection
  o LossDataSink
- clean up
- splitting Options into classic and opal options

- putting own header file first
  o for reason see http://www.cplusplus.com/forum/articles/10627/#msg49679 and
                   http://www.cplusplus.com/forum/articles/10627/#msg49680

- remove 'using namespace' from header files
- remove 'using std::string' and 'using std::abs' from header files

For reason see:
o http://stackoverflow.com/questions/5849457/using-namespace-in-c-headers

- use forward declaration where possible
- remove unused includes

    - starting to use smart pointers and other c++11 features (adapted flags cmake file)
    - adapting slice tracker to fit new t-t layout