All OpenSeadragon contributors have granted their permission for this
relicensing in #58.
Drop copyright statements for Ian Gilman and Christopher Thatcher as
they requested in #10.
Revert CodePlex Foundation copyright date to 2009 pursuant to discussion
in #10.
It's convenient for old releases to be available indefinitely so that
deployment scripts can retrieve a particular qualified version. This
won't affect the disk space requirements of the repository, since the
old packages will be in the Git history anyhow.
Move packages to a subdirectory of the site root to avoid causing
permanent clutter.
Tar files are conventionally compressed, often with gzip. xz would be
better but is not as universally supported; in particular,
grunt-contrib-compress doesn't support it.
