Add .scalarDivide to Matrix and Vector classes

[jbrown1618]

This is not technically a real matrix operation, but it is commonly needed, particularly for scaling. Right now, the approach commonly used is:

const inverse = ops.getMultiplicativeInverse(scaleFactor);
if (inverse === undefined) return someDefault;
return vector.scalarMultiply(inverse);

But this introduces a little bit of numerical error - 10 * (1/3) is less accurate than 10 / 3. We will need to re-implement NumberOperations.divide to get this to work correctly.

In particular, this will make the gauss-jordan equation solver more accurate.

[jbrown1618]

First attempt resulted in worse accuracy for some operations. This could be a fun investigation for a rainy day.