threw out the spin symmetry optimization to prepare for the implementation of the particle-hole transformation (will check later if I can make the two compatible, but for now lets just do it the easy way ...)
initial and untested implementation of the particle hole transformation
fixed an underflow bug in the TVector class; calculation of the chemical potential now ensures the right number of spin up/down particles in the determinantal part
switched single particle orbital calculation to double precision; removed an unnecessary function from mccrun_prepare
switched Jastrow class from storing exp(v_ij) to storing v_ij (it was an optimization that was actually slower after the p.h. transformation); evaluation of the log derivatives now also uses the Jastrow as m_i*m_j (dropped the +1 that was related to the normalization)