Beta 2.1

Input now supports negative numbers
Negative number must be either at the beginning (example: -9-1=-10) or inside brackets (example: 9-(-9)=18)

Beta 3

Added deg and rad functions to easily convert radians into degrees and vice-versa

Beta 1

The calculator is working, I think it's ready to be released.
Zip contains both files so you don't have to download them separately