Added diff command to the installer.
Added per-file operations to the installer.
Installer now defaults to diff operation when no operation is supplied.
Installer warns if .bash_profile already exists.
Incorporated setup for appengine tools.
Added .bashrc and .bash_aliases.
Added export to of environment variables to finder.
Added notes about what to install.
Added 'go' (language) to PATH and set up GOPATH.