C++: Step 5 of the std::string transition. Hopefully the last step. Move to using std::string and std::vector for almost everything we can. Only the the file read buffer is still using C style basic character buffers. Undecided if I want to move that to std::string so considering it done for now. Add /EHsc to the compiler options for Visual C to use std::vector::push_back.

# Set these here to change the version for all platforms
DW_MAJOR_VERSION=3
DW_MINOR_VERSION=3