[scripts-audit] vcpkg.cmake (microsoft#16061)

* [vcpkg.cmake] modify to get in line with the audit

See PR microsoft#16055

This also (attempts to) allow vcpkg.cmake to run with cmake 3.0; we had
a VERSION_GREATER_EQUAL check, but that if keyword was added in cmake
3.7.

* s/target_name/package_name in find_package

* depend on z_vcpkg_function_arguments

instead of a custom macro
also, as a drive-by, switch to foreach(X IN LISTS ...)

* split the utility macros/functions out

additionally, move the options and settings to the top of the file

* move more options and settings to the top

* fix name of file

* fix ras code comments

* remove z_vcpkg_utilities due to export
* add cmake_policy(PUSH|POP)
* add VCPKG_INSTALLED_DIR input variable
* add .cmakestamp to vcpkg_installed

* fix osx ifs to use quotes

also, remove spaces between if and (, to keep style consistent
(mostly for ease of grepping...)

* fix bug fixed by microsoft#16193

* move z_vcpkg_add_fatal_error up

* fix RANGE for reals