add readme

Author: vrischmann

README.md

@@ -0,0 +1,22 @@
+# picohttpparser
+
+This is https://github.com/h2o/picohttpparser packaged for [Zig](https://ziglang.org)
+
+# Installation
+
+Use `zig fetch`:
+
+```
+zig fetch --save git+https://github.com/vrischmann/zig-picohttpparser-sys#master
+```
+
+You can then import `picohttpparser` in your `build.zig`:
+```zig
+const picohttpparser = b.dependency("picohttpparser", .{
+    .target = target,
+    .optimize = optimize,
+});
+
+your_exe.addIncludePath(picohttpparser.path("."));
+your_exe.linkLibrary(picohttpparser.artifact("picohttpparser"));
+```