This reverts commit c5bea524.

This reverts commit b18f6cc1.

sub-models:
- now derived from a common base class
- copy/clone functionality added

cloud:
- makes use of cachedRandom class (instead of Random)

Needs dTarget data member in KinematicParcel.

Some functions in InjectionModel no longer const.

Squashed merge of particleInteractions up to
commit e7cb5bcf0315c359539ef1e715e1d51991343391

to KinematicParcel incorporating latest master branch changes.

- Added helper classes to simplify the handling of the injector properties
- Added new reacting multiphase injection model variant

  Injection:
  - moved position and velocity constraints for 2-d cases to the base InjectionModel
  - added validInjection function

  Clouds
  - added an effective density function to the KinematicCloud

    - injection model sets new parcel position and cell owner
    - allows injection model to cache injection cells etc.

 - it also found things like size_t instead of size_type in fileName class