Update README.md

Author: omgaz

README.md

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 js-diff
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+[![Build Status](https://travis-ci.org/omgaz/js-diff.svg?branch=master)](https://travis-ci.org/omgaz/js-diff)
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 A basic JavaScript object comparison script that will iterate, recursivly, through two JSON objects to compare differences.
 
 This was built for a project in which I had a JSON object of user data that I cached on page load and compared against an edited version on save. I used this information to construct email summaries of changed behaviour as well as provide a detailed audit trail of actions.