- Pathname,PathInfo

- Pathname,PathInfo
  - Classes and associated types were moved into namespace
    zypp:fileststem.
  - static PathInfo methods operating on files/dirs were moved
    into namespace zypp:fileststem (now outside class Pathinfo).
  - classes Pathname,PathInfo are still available in
    namespace zypp.
- removed stringutil.{h,cc}
  Usefull stuff was moved in to namespace zypp:str (String.h)
- added base/IOStream.h
  std::stream related utilities in namespace zypp:iostr.
  - getline: Read one line from stream.
  - forEachLine: Simple lineparser: Call a functor for each line in file.
- added base/Fd.h
  safe handlich of oen()/close() on filedescriptors.
- media/*
  - Fixed MediaException decl.
  - Fixed MediaAccess::Ptr/consPtr (should be intrusive_ptr
    as class is derived from ReferenceCounted)
  - Fixed all code locations which throw, to use ZYPP_THROW