Update README.md

Looks like the first example had the wrong command.
Merge pull request #1 from AWinterman/patch-1

jsdom -> jsdom-eval in the readme.
jsdom version bump
0.0.2
Merge branch 'master' of github.com:hayes/jsdom-eval
sourcemap support
cleanup
fixed dep, docs
0.0.3
bad dep
0.0.4
better sourcemap stacktraces
0.0.5
updated docs
0.0.6
better stack trace
0.0.7