fenestroj

Easier wrappers for winapi stuff.

• Function naming follows the Rust snake_case convention: GetLastError becomes get_last_error
• Function names for direct function wrappers are otherwise identical to the winapi function name.
• Functions that are "new" to this crate (such as wide_null) just have whatever name seems appropriate.
• Functions are made safe if it's easily possible, and the rest of the time I just try to document the unsafe elements.