If a call to `vcpkg_replace_string` makes no changes i.e doesn't
effectively replace a string, A warning is logged.
This should also help identify ports that no longer need these calls to
fix things in `.pc` files etc.
* [docs] Delete embedded documentation in favor of docs/
Drive-by for the helper ports:
1. "documentation": "https://vcpkg.io/en/docs/README.html"
2. "license": "MIT"
3. Use `include_guard(GLOBAL)` in all script files
4. Make sure any persistent variables are saved to the cache
* [docs] Restore empty regenerate.ps1 to satisfy Azure Pipelines
* [docs] PR comments
* [vcpkg docs] Change how documenting port functions works
Instead of using `##`, use comment blocks for documentation.
Also, add some minor docs and change RST -> MD
so we actually get docs generated.
* add CI stuff
* regenerate docs
* fix vcpkg_find_acquire_program to not use _execute_process
