add package cgetopt (#138)

packages/c/cgetopt/xmake.lua

@@ -0,0 +1,15 @@
+package("cgetopt")
+
+    set_homepage("https://github.com/xq114/cgetopt/")
+    set_description("A GNU getopt() implementation written in pure C.")
+
+    add_urls("https://github.com/xq114/cgetopt/archive/v$(version).tar.gz")
+    add_versions("1.0", "c93fe91041752f4231e07894d24354ee079317e40c30897bd664766ef4872279")
+
+    on_install(function (package)
+        import("package.tools.xmake").install(package)
+    end)
+
+    on_test(function (package)
+        assert(package:has_cfuncs("getopt", {includes = "getopt.h"}))
+    end)