a rough draft of the linesweep lab
cut out the part on binary trees, added the multidimensional problem.
Changed formatting.
re-added a problem on binary trees. It turns out they are pertinent for
sleightly higher dimensional cases.
added a useful comment to one of the problems.
added solutions to linesweep lab
Sleight phrasing change in linesweep lab.
This is a major update to the linesweep lab. It accounts for a few more
possible ways to code the algorithm.
futher clarified explanation of linesweep algorithms

Also made some other small changes to the lab.
futher changes to enhance clarity
wrap figures and change enumerate

Wrapped each figure in a figure environment.  This greatly improves the
layout.
Added some benchmarks and the code to generate the plots to the solutions
notebook.
Merge pull request #4 from ayr0/sweepline

updates to line sweep lab
fixed some typos and formatting issues in the linesweep lab.
Note: added dependency on paralist package.
Removed old image files from linesweep lab.
Added new pdf versions of the plots.
Updated the linesweep lab, its solutions, and its plots to reflect some
implementation changes in the algorithms.
Sleight change in last problem.
fix path written to template

subimport expects paths to be posix-like.  This breaks on windows.  We
therefore have to replace all windows path separators to posix ones.
Generally, this is a big no-no, but is unavoidable in this case.
Merge pull request #60 from ayr0/makelab

fix path written to template
missing }