chore(docs): fixed typo

Fixed typo (removed extra 'to') and added colon to match other steps in global installation instructions.
Close angular#2190

Author: btroncone

README.md

@@ -357,7 +357,7 @@ First install Bootstrap from `npm`:
 npm install bootstrap@next
 ```
 
-Then add the needed script files to to `apps[0].scripts`.
+Then add the needed script files to `apps[0].scripts`:
 
 ```
 "scripts": [