Adding `photo-name` executable...

This could do with a lot of cleaning up, and it's not
yet cabable of auto-detecting the photo dates, but it's
better than nothing.
Bashrc: Don't use virtualenvwrapper in every shell...

The bash completion script takes too long to run, so don't
source it automatically.  Instead, wait until the first
invocation of `workon`, and then source it.