Merge codebase

When I left NESCent, I deposited TreeTapper's code in Google Code ( http://code.google.com/p/treetapper/ ). Subsequent development happened on a privately-hosted version of that code (I was worried about accidentally committing a file with database access passwords). I've since learned a lot more about SVN and have svn:ignored the dangerous files, as well as files that aren't really things to put in version control, such as cached images. Now, changes made on the Google Code repository will be made live on the site. This should make it easier to collaborate with others going forward.