some minor changes

There's one improvement I made - for x86_64, having TConfig a 64 bit variable helps slightly with the instruction count in CEvaluator::EvalMobs (the tool I wrote for the Clang/llvm bug is helping me with tiny incremental changes in code quality). Because TConfig is only used in one file, I got rid of the underlying header file.

Other than that: just minor cleanups such as getting rid of unused variables, but also a proper initialization in Search.cpp: double tElapsed = 0.0;