spacing fixes in the householder lab.
Explained choice of v in householder lab.
Revised pseudocode in householder lab to avoid increasing the complexity
of the algorithm.
Added a description of how to use householder reflections to compute Q.
Added a warning to avoid a potential pitfall in Householder code.
Updated discussion on stability in Householder lab.
Also made some small changes to the section on Hessenberg matrices.
Fixed compile error.
Namespace, spacing, and style fixes in Householder solutions.
A few more small changes to Householder solutions.
Replaced householder qr solution with an updated solution.
Some fixes to the householder solution I just added.
Removed givens solution form Householder lab.
Redid Hessenberg solution to fix order of complexity.
Merge pull request #338 from insertinterestingnamehere/householder

Householder