Args: Update compute_program_name_loc to take ArgumentState* as an arg and simplify
Args: Rename arg_state to sArgState
Drop chplBinaryName; rely on sArgState.program_name
Args: Rename compute_program_name_loc() to init_args() and move it to arg.cpp.  Call init_args before main AST init
Final cleanup
Merge pull request #1058 from noakesmichael/arg-0

Refine initialization with emphasis on ArgState

Primarily convert compute_program_name_loc() in driver.cpp to init_args() in arg.cpp and then some
associated cleanup.

Finally removed the handful of dedicated timers in driver.cpp per discussion a long time ago.

Compiled: STD clang/darwin, STD gcc/linux64, LLVM gcc/linux64
Tested: paratest --verify
Review: none