Examples for no_std windows-sys.

There are three crates here:

• nostd A normal no_std application.
• nocrt A no_std application without CRT startup. It does however use some vcruntime provided methods.
• novcrt A no_std application without CRT startup or the vcruntime library. This requires defining our own memcpy, etc functions.

Note that all but nostd are very unusual configuration. Even in a no_std application you'd usually want the CRT.

novcrt is by far the most niche as it does not even use the vcruntime (but I'm uncertain why you'd want this). Maybe if you can write better mem* implementations than Microsoft.