Update README.md to reflect 'library' terminology instead of 'software'

Author: nikoscham

README.md

@@ -4,7 +4,7 @@
 
 ![website status](https://img.shields.io/website?url=https%3A%2F%2Ffeascript.com%2F)
 
-FEAScript is a finite element simulation software developed in JavaScript. This is the source code of the FEAScript <a href="https://feascript.com/" target="_blank">website</a>.
+FEAScript is a finite element simulation library developed in JavaScript. This is the source code of the FEAScript <a href="https://feascript.com/" target="_blank">website</a>.
 
 ## License