make initial implementation

credit
- https://github.com/AlphaModder/include-lua

tests/tests.rs

@@ -0,0 +1,26 @@
+use rlua::Lua;
+use rlua_searcher::{AddSearcher, Result};
+use std::collections::HashMap;
+
+#[test]
+fn it_works() {
+    let lume = read_lume_to_string();
+    let name = "lume".to_string();
+    let mut map = HashMap::new();
+    map.insert(name, lume);
+
+    let lua = Lua::new();
+
+    let hello = lua
+        .context::<_, Result<String>>(|lua_ctx| {
+            lua_ctx.add_searcher(map)?;
+            Ok(lua_ctx.load(r#"return require("lume")"#).eval()?)
+        })
+        .unwrap();
+
+    assert_eq!("hello lume", hello);
+}
+
+fn read_lume_to_string() -> String {
+    r#"return "hello lume""#.to_string()
+}