https://www.seleniumeasy.com/selenium-tutorials/how-to-extract-pdf-text-and-verify-using-selenium-webdriver-java
http://roadtoautomation.blogspot.in/2013/04/road-to-verify-pdf-file-text-using-java.html
http://stackoverflow.com/questions/941813/how-can-i-determine-if-a-file-is-a-pdf-file