`tools/test-js-with-node cover` needs istanbul to be installed in
order to work; we might as well install it by default rather than
having it be an extra step users need to deal with.
Of course, since this is only needed in the development environment,
this could suggest we want to fork/conditionalize package.json, but I
think for now it's reasonable to just install everything we use
somewhere -- the npm list is still pretty short and we have that issue
anyway with webpack-dev-server.
The node packages 'jQuery' and 'jquery' are different--'jQuery' is the
legacy support package that is needed for Zulip so the require statements
in the tests were updated.
Travis uses node 4.0 by default and we are using 0.10, so the command to
install the correct version had to be added to the .travis.yml file.
Umair Khan
Tim Abbott
Allie Jones