Typo error fix and updated repo names.

README.md

-# document-convert
+# file-convert
 
-[![Build Status](https://travis-ci.com/kalimuthu-selvaraj/document-convert.svg?branch=master)](https://travis-ci.com/kalimuthu-selvaraj/document-convert) [![Coverage Status](https://coveralls.io/repos/github/kalimuthu-selvaraj/document-convert/badge.svg?branch=master)](https://coveralls.io/github/kalimuthu-selvaraj/document-convert?branch=master)
+[![Build Status](https://travis-ci.com/kalimuthu-selvaraj/file-convert.svg?branch=master)](https://travis-ci.com/kalimuthu-selvaraj/file-convert) [![Coverage Status](https://coveralls.io/repos/github/kalimuthu-selvaraj/file-convert/badge.svg?branch=master)](https://coveralls.io/github/kalimuthu-selvaraj/file-convert?branch=master)
 
 Converts `.ppt` `.pptx` `.odp` and `.key` file to `pdf or/and image(png, jpg, jpeg and etc..)`