Fix typo in README (#76)

it ain't much, but it's honest work ;)

README.md

@@ -20,7 +20,7 @@ Change the name of the crate: Chose a good name for your project, and change the
 * `main.rs`
     * Change `eframe_template::TemplateApp` to `your_crate::TemplateApp`
 * `index.html`
-    * Chage the `<title>eframe template</title>` to `<title>your_crate</title>`. optional.
+    * Change the `<title>eframe template</title>` to `<title>your_crate</title>`. optional.
 * `assets/sw.js`
   * Change the `'./eframe_template.js'` to `./your_crate.js` (in `filesToCache` array)
   * Change the `'./eframe_template_bg.wasm'` to `./your_crate_bg.wasm` (in `filesToCache` array)