download gemspec.rz file on fetch, because so many gem files can generate gemspec.rz by "gem generate_index" command, this will be error and break.
Fetch others spec file on mirror.
Add bundler
Mirror yaml, yaml.Z file.
Disable delete gem feature.
Disable delete feature.
prerelease mirror, from #6
Update README to markdown format.
Don't write file, when response body length equal zero.
Rakefile didn't work, don't recall the error now.  mirror.rb changes are from a github pull request to fix binary packing/unpacking on windows.
look for missing *spec.rz files in the same fashion we look for missing .gem files
Merge branch 'master' of github.com:lamont/rubygems-mirror

Conflicts:
	lib/rubygems/mirror.rb