Merge pull request #3 from vedharish/install_testem_in_readme

Add instruction to install testem in README

Author: nidhimj22

README.md

@@ -9,6 +9,6 @@ Instructions
 1. Get a [BrowserStack](browserstack.com) account.
 2. For BrowserStack Authentication export the environment variables for the username and access key of your BrowserStack account. These can be found on the automate accounts page on [BrowserStack](https://www.browserstack.com/accounts/automate) `export BROWSERSTACK_USERNAME=<browserstack-username> && export BROWSERSTACK_KEY=<browserstack-access-key>`
 3. Install the dependencies by running `npm install browserstack browserstacktunnel-wrapper`
-4. Run the command `testem ci -l bs_chrome` to test out the setup with just the Chrome browser hosted BrowserStack.
-5. Run `testem ci` to run it on all the listed browsers - see `testem launchers` for the full list.
-
+4. Install testem globally by running `npm install testem -g`
+5. Run the command `testem ci -l bs_chrome` to test out the setup with just the Chrome browser hosted BrowserStack.
+6. Run `testem ci` to run it on all the listed browsers - see `testem launchers` for the full list.