optional-lite: add package (#2469)

* optional-lite: add package

* fix test

packages/o/optional-lite/xmake.lua

@@ -0,0 +1,21 @@
+package("optional-lite")
+    set_kind("library", {headeronly = true})
+    set_homepage("https://github.com/martinmoene/optional-lite")
+    set_description("optional lite - A C++17-like optional, a nullable object for C++98, C++11 and later in a single-file header-only library")
+    set_license("BSL-1.0")
+
+    add_urls("https://github.com/martinmoene/optional-lite.git")
+    add_versions("2023.05.11", "00e9cf5ca5a496e857bc6a28ffed9f4189ce6646")
+
+    on_install(function (package)
+        os.cp("include", package:installdir())
+    end)
+
+    on_test(function (package)
+        assert(package:check_cxxsnippets({test = [[
+            #include <nonstd/optional.hpp>
+            nonstd::optional<int> test() {
+                return nonstd::nullopt;
+            }
+        ]]}, {configs = {languages = "c++11"}}))
+    end)