Started meeting handout

For weekly meetings, the client wants to be able to print out a page with the
names, emails, and pictures of every student, sponsor, and instructor involved
in a team. This way, at the beginning of the semester, they can print these
handouts out to make it easier for everyone to get to know each other.

This commit introduces some of the functionality to create this handout. The
meeting_handout.html.haml file is going to need to be edited to look better in
the future, probably so that it uses a printer-friendly layout and its own CSS
styling.
New layout for meeting handout printout

This commit gives the teams_controller#meeting_handout action a new,
page-specific layout, located at app/views/layouts/meeting_handout.html.haml. In
addition, it modifies the asset pipeline by creating a meeting handout-specific
pipeline manifest, app/assets/javascript/meeting_handout.js, and including in it
a meeting handout-specific CSS file, app/assets/stylesheets/meeting_handout.css.

This commit relies on a few images which I have *not* committed. Download the
UNL wordmark and campus logo from http://ucomm.unl.edu/our-marks, then put the
colored and black-and-white versions of both (JPG format) into
app/assets/images. Rename the files to wordmark_colored.jpg, wordmark_bw.jpg,
campus_logo_color.jpg, and wordmark.jpg. I didn't include them because I'm not
sure UNL is OK with its logos being committed into an open-source repository. I
sent an email asking, and if they get back to me with an OK, I'll add the images
to the repository.

If you want more details about what I did in this commit, I summarized my
research and the types of changes I made in this StackOverflow thread:
http://stackoverflow.com/questions/27206835