Updates README with Travis Cl status

Minor changes
    + Adds Travis Cl integration status image
    + Renames title section

README.md

@@ -1,6 +1,5 @@
-> Released version 0.3.5
+## libgost15 [![Build Status](https://travis-ci.org/aprelev/libgost15.svg?branch=master)](https://travis-ci.org/aprelev/libgost15)
 
-### Description
 
 Year 2015 introduced new national block cipher standard GOST 34.12 '15, which goes by codename Grasshopper (**Kuznechik** as in **Kuz**min, **Nech**aev and **K**ompany).