Add C++ library Proxy (#1534)

Author: mingxwa

bin/yaml/libraries.yaml

@@ -1993,6 +1993,16 @@ libraries:
         - ./autogen.sh
         - ./configure
       type: github
+    proxy:
+      check_file: proxy.h
+      method: clone_branch
+      repo: microsoft/proxy
+      targets:
+      - 3.0.0
+      - 3.1.0
+      - 3.2.0
+      - 3.2.1
+      type: github
     pugixml:
       build_type: cmake
       check_file: README.md

windows/msvce-config.json

@@ -239,6 +239,11 @@
         "description": "Parsing Expression Grammar Template Library",
         "pretty_name": "PEGTL"
       },
+      "proxy": {
+        "url": "https://github.com/microsoft/proxy",
+        "description": "C++20 Polymorphism Library",
+        "pretty_name": "Proxy"
+      },
       "pugixml": {
         "url": "https://github.com/zeux/pugixml",
         "description": "pugixml is a C++ XML processing library",