Standard least squares, min || Ax - b ||_2

Modules
	gels: least squares using QR/LQ
	gelst: least squares using QR/LQ with T matrix
	gelss: least squares using SVD, QR iteration
	gelsd: least squares using SVD, divide and conquer
	gelsy: least squares using complete orthogonal factor
	getsls: least squares using tall-skinny QR/LQ
	--- auxiliary ---
	laic1: condition estimate, step in gelsy
	lals0: back multiplying factors, step in gelsd
	lalsa: SVD of coefficient matrix, step in gelsd
	lalsd: uses SVD for least squares, step in gelsd

Detailed Description