msvc bugfix: renaming unit_type::HELP_INDEX to prevent naming conflicts with a marco in a windows header
msvc bugfix: specify explicit namespace in formula_tokenizer::TOKEN_TYPE to prevent naming conflicts with an enum in a windows header
use explicit ansi version of windwos functions if the arguments are ansi
msvc bugfix: http://connect.microsoft.com/VisualStudio/feedback/details/520043/
msvc bugfix: fixing a bug related to save_index and config cache that cause wesnoth to crash if compiled with visual studio.