enhance the trap distribution and occupation control

- NEW : add the parameters for trap distribution and occupation and its related methods
- MEW :add 2D distribution of traps
add Poole-Frenkel detrapping mechanism

- NEW : add related methods to read and store newly-added parameter
- NEW : add new material property
- NEW : add the switch for Poole-Frenkel model
add new parameters
add interface trap distribution for debugging
add timing mechanism

- NEW : add method to output total time and the time used by each solver
- ENH : enhance Sctmtimer
fix a bug in timer

- FIX : clock() return clock_t, which is another name of long, convert to double before being used
tiny revision based on last commit
Merge branch 'timeSolvers'

Conflicts:
	SctmUtils.cpp
tiny revision on SctmTimer