Add JavaScript version

Provide JavaScript function to draw Paley graph; assumes an object paley exists
with fields p and canvas, representing the order of the Paley graph to draw and
an HTML 5 canvas on which to draw it.

Fixes #2
Wrap Paley functionality in newPaley() function

Returns an object containing p, a reference to the canvas, and the draw() function
Correctly call clearRect()

I had forgotten to provide the coordinates of the upper-left corner
Fix stupid error in paley.js

The name of the iteration variable in the inner loop of draw() was residue, but
I had erroneously referred to it as j in the incrementation and conditional parts
of the for loop.
Add simple HTML sample to demonstrate paley.js
Update README.md
Merge branch 'paley-js' into paley-master