Update gradecalc.js

Added license

Fixed input capture issue and empty grades issue

Spaces at the end of category names are trimmed and multiple spaces separating words are replaced by one

Grade calculator now calculates and is minified

Numbers are now floats and not ints. Category percentage sum now has to be < 100

Added rewrite of all selection options after removing category

fixed a newline

Added css normalization and styling to calculator

Fixed the issue of not being able to edit the first assignment label.

Fixed alignment of code in index.html

Added the calculate button and appropriate heading with span area for result. Closes #005

Calculator now shows one assignment at initialization. Added html to index page and increased count of assignment numbers to reflect the first assignment.

Fixed some jQuery for working category data

Initial addition of files