add hole trap solver

- NEW : add a new trap solver for hole especially for the conservation of holes
- NEW : add related math method for the new trap solver
- NEW : add several new physical and trap properties
- NEW : add a new parameter for uniform hole densiy
debug the new hole solver

- NEW : add the methods to write hole information
- NEW : debug the hole trapping solver
enhance the existing trap solver to consider hole trapping

- NEW : add the consideration of holes in the former trap solver
- ENH : enhance the existing trap solver
- NEW : separately consider electrons and holes in the dd solver
debug the trapping solver and dd solver with the contribution of holes

- FIX : fix a bug in obtaining hCurrentDensity
- FIX : fix a bug when refreshing trapped hole density in trapping solver
- NEW : add holes contribution of charge in net charge and net trapped charge
- NEW : add the method of writing tunneling information at the interface
add a new trap solver to solve the electron hole interaction

- NEW : add new parameters for trapped electron and hole cross-section
- CHG : rename some names, electron trap cross-section --> electron cross-section; the electron trapped cross-section is now for the trapped electron and hole cross-section
- NEW : add the method to write tunneling information, including tunneling coefficient or tunneling current density
- NEW : add a new class for solving electron trapping, hole trapping and the interaction between them
work on the trapping solver of interaction of electrons and holes

- NEW : add a new method to solve linear equations with two variables/
- NEW : add the new trapped electron/hole capture coefficient
- FIX : the trapped electron capture coefficient is related to hole velocity
- NEW : add the method for setting combined solver for trapping.
debug the combined solver for electron and hole trapping/de-trapping

- NEW : implement the combined trap solver
- ENH : enhance the DD solver to consider holes de-trapping
- NEW : add new physical parameters for hole de-trapping
- FIX : the name for parameter trapped hole cross-section is fixed
- NEW : use combined solver in solver pack
- NEW : add de-trapping mechanisms in combined trap solver