* src/gdcmHeader.cxx RecupLgr split in FindVR and RecupLgr. FindVR

  * src/gdcmHeader.cxx RecupLgr split in FindVR and RecupLgr. FindVR
        concentrates on finding the value representation (when it exists).
        RecupLgr now only finds the element value length, and it avoids
        returning the unecessary skL (skipped length).
        Also, offsetCourant was simply removed (with taille_fich) since
        it was redundant with the File position internals (by using
        ftell and fseek). This also made skL (see above in RecupLgr) usage
        jajun.
      * src/gdcmHeaderIdo.cxx src/gdcmIdo.h added. Those files concentrate
        on the libido specificities which are handled through class
        inheritance.
      * Test/implicit_vr.dcm dicom v3 in implicit value representation
        added.   --- Frog