add the detrapping mechanism according to basic SRH theory

- NEW : add the method for updating rhs vector in dd solver
- ENH : delete existed files using Python script in the beginning of the simulation
- CHG : change the consideration of effective density of state. move it to the vertex physics
- NEW : add the corresponding trap property
- NEW : add the method for datrapping mechanism in trap solver
- ENH : use the silicon effective mass for trapping in tunnel solver when calculating tunneling problems