Completed Distributions lab.
minor formatting changes
Made more edits to vol 2 lab 1.
Fixed the namedtuple example code.
Merge pull request #1 from ayr0/jared-distributions

Formatting changes
Merge pull request #306 from abefrandsen/student_edits

Student edits
Merge pull request #301 from jareddf/distributions

Completed Distributions lab.
Merge pull request #305 from insertinterestingnamehere/numpy

Tentative shortening of the NumPy lab.