Added clover inversion routine.
Added public Dirac::Dagger() to change dagger in Dirac operator.
Initialised siteDim to prevent compiler warnings.
Added new QUDA interface function invertMultiShiftMDQuda for doing multi-shift and the subsequent dslash applications.  Clover inversion is called in loadCloverQuda if clover inverse is not passed in.  Hack to return inverse field in odd sites of clover field when inverse is computed (for TIFR-MILC RHMC).