Modify example code to work out of the box

When testing the old example code I would get the following error:

const drives = await drivelist.list();
               ^^^^^
SyntaxError: await is only valid in async function

I have modified the example code so you can cut, paste and run without error.

README.md

@@ -29,8 +29,12 @@ Examples (the output will vary depending on your machine):
 ```js
 const drivelist = require('drivelist');
 
-const drives = await drivelist.list();
-console.log(drives);
+getDrives();
+
+async function getDrives () {
+ const drives = await drivelist.list();
+ console.log(drives);
+}
 ```
 
 ***
@@ -176,10 +180,14 @@ Documentation
 ```js
 const drivelist = require('drivelist');
 
-const drives = await drivelist.list();
-drives.forEach((drive) => {
- console.log(drive);
-});
+getDrives();
+
+async function getDrives () {
+ const drives = await drivelist.list();
+ drives.forEach((drive) => {
+ console.log(drive);
+ });
+}
 ```
 
 Tests