add cosmocc (#3240)

* add cosmocc

* add mirror

* improve test

* fix windows

* add more platform

* call sh

* improve copy

* fix test

packages/c/cosmocc/xmake.lua

@@ -0,0 +1,17 @@
+package("cosmocc")
+    set_kind("toolchain")
+    set_homepage("https://github.com/jart/cosmopolitan")
+    set_description("build-once run-anywhere c library")
+
+    add_urls("https://cosmo.zip/pub/cosmocc/cosmocc-$(version).zip",
+             "https://github.com/xmake-mirror/cosmopolitan/releases/download/$(version)/cosmocc-$(version).zip")
+    add_versions("3.2.4", "d2fa6dbf6f987310494581deff5b915dbdc5ca701f20f7613bb0dcf1de2ee511")
+
+    on_install("@macosx", "@linux", "@bsd", "@cygwin", "@msys", function (package)
+        os.cp("*", package:installdir(), {symlink = true})
+    end)
+
+    on_test(function (package)
+        local cosmocc = path.join(package:installdir("bin"), "cosmocc")
+        os.vrunv(cosmocc, {"--version"}, {shell = true})
+    end)