Clear local storage data upon new version of AS

#### To test:
 - npm install
 - grunt build
 - Run your web app with recently compiled version of AS and make sure that local storage has new  AS_version key that matches with its compiled version from package.json. 
Why are you using the non-capturing parentheses here? Also, why are you making the regular expression case-insensitive? I think that we should absolutely be sensitive to case, after all our context it always `AS/` not `as/` or `As/`.

This could be simplified to look something like:
````
regExp = new RegExp "^#{@keyContext}"
````