Removed Astropy units for now.

Python has trouble converting units to scalars and back. We don't need
them for now so just get rid of them until at least we know the ALI
process works correctly.
Removed extra spaces around equals sign in main().
ALI works! (I think?!)

I think the part that was wrong before was a "1" that should have been an
identity matrix. In the former case, writing

			1 - A

where A is a matrix, results in each matrix element having the value

			A_ij -> A_ij - 1

but if using the identity matrix then we have

			A_ii -> A_ii - 1
			A_ij -> A_ij

The reason I used a 1 in the first place is because that's how it's frequently
written in the literature, even though it's always implied that 1 is actually
the identity matrix I.