added selenium/chromedriver binary

Added dryad-repo/selenium/bin directory and added Chrome driver
binary at version 2.10 for OSX to support running Selenium
tests against Chrome.
updated selenium/pom.xml for most recent selenium version

Bumped Selenium-Java dependency version up to most recent
version (2.42.2) to support most recent version of Firefox. Support
for most recent version of Chrome is erratic.

Also added flag for '-DseleniumTestURL' to enable setting
browser to be tested in the command as the test url is.
added more extensive tests for author editing and reordering

Added fuller testing of author name and order editing, and added
code to have the test run clean up after itself if possible.
added some documentation to selenium/runtests.sh

Added a bit of documentation to the selenium run-all-tests script
around Chrome testing.