Windows support

- Implements basic VT100 parsing for fg and bg colors (among other attributes, only underline and reversed-color could be supported but currently aren't).
- Implements `cwrite` family

 How it works:
   - instantiate a VT100 parser and saves current console attributes
   - parse characters one by one searching for escape sequence and colour the console accordingly, write char one by one, flushes at colour change
   - restore original console attributes

 (`cprintf` was originally planned but it turned out to be harder).

- Compatible with both DMD 2.065 and 2.066 by moving `@nogc` before the functions.

- I took the liberty to add more files and use `module` names, I guess everything could go in one file if you wish.