Update README

Cargo.toml

@@ -1,12 +1,14 @@
 [package]
 name = "luajit2-sys"
-description = "LuaJIT-2.1 FFI Bindings"
 version = "0.0.1"
+description = "LuaJIT-2.1 FFI Bindings"
 authors = ["Aaron Loucks <aloucks@cofront.net>"]
 edition = "2018"
 keywords = ["lua", "luajit", "script"]
 license = "MIT OR Apache-2.0"
+readme = "README.md"
 repository = "https://github.com/aloucks/luajit2-sys"
+documentation = "https://docs.rs/luajit2-sys"
 links = "luajit"
 
 [dependencies]

README.md

@@ -1,3 +1,47 @@
 # Rust LuaJIT 2 Bindings
 
-[![Build Status](https://dev.azure.com/aloucks/aloucks/_apis/build/status/aloucks.luajit2-sys?branchName=master)](https://dev.azure.com/aloucks/aloucks/_build/latest?definitionId=3&branchName=master)
+[![crates.io](https://img.shields.io/crates/v/luajit2-sys.svg)](https://crates.io/crates/luajit2-sys)
+[![docs.rs](https://docs.rs/luajit2-sys/badge.svg)](https://docs.rs/luajit2-sys)
+[![build](https://dev.azure.com/aloucks/aloucks/_apis/build/status/aloucks.luajit2-sys?branchName=master)](https://dev.azure.com/aloucks/aloucks/_build/latest?definitionId=3&branchName=master)
+
+```toml
+[dependencies]
+luajit2-sys = "0.0.1"
+```
+
+## Exported Cargo Environment Variables
+
+|||
+| -- | -- |
+| `DEP_LUAJIT_INCLUDE`  | Path to the LuaJIT source and headers |
+| `DEP_LUAJIT_LIB_NAME` | Platform specfic lib name (`lua51` on Windows and `luajit` everywhere else) |
+
+## Example
+
+```rust
+use luajit2_sys as sys;
+use std::ffi::CStr;
+
+fn main() {
+    unsafe {
+        let lua = sys::luaL_newstate();
+        sys::luaL_openlibs(lua);
+        let script_data = b"return 1 + 2";
+        let script_name = b"run_script\0";
+        sys::luaL_loadbuffer(
+            lua,
+            script_data.as_ptr() as _,
+            script_data.len() as _,
+            script_name.as_ptr() as _,
+        );
+        sys::lua_pcall(lua, 0, 1, 0);
+        let idx = sys::lua_gettop(lua);
+        let s = sys::lua_tostring(lua, idx);
+        let result = CStr::from_ptr(s).to_string_lossy().to_string();
+        sys::lua_close(lua);
+
+        println!("result: {}", result);
+    }
+}
+```
+