Update README.md

Just a minor discrepancy in the "Detailed Installation Instructions" link. It's (http://edu.biojs.net/series/101/20_getting_started.html) instead of (http://edu.biojs.net/series/101/02_getting_started.html). Could you please merge this.
Merge pull request #106 from DevasenaInupakutika/patch-1

Update README.md