most basics of readme

README.md

@@ -0,0 +1,27 @@
+# Ivory
+
+Writing php extensions in rust
+
+## Usage
+
+```
+use ivory::{ivory_export, ivory_module};
+use ivory::externs::printf;
+
+#[ivory_export]
+fn hello_other(other: String) {
+    printf(format!("Hello {}", other));
+}
+
+#[ivory_export]
+fn hello_world() {
+    printf("Hello world, Rust2!");
+}
+
+ivory_module!({
+    name: "demo",
+    version: "0.0.1",
+    functions: &[hello_world, hello_other],
+    info: &[("demo extension", "enabled")]
+});
+```