Remove docs and point to ones on dartlang.org.

app/doc/pub-uploader.markdown

----
-title: "Command: Uploader"
----
-
-    $ pub uploader [options] {add/remove} <email>
-
-This command allows [uploaders](glossary.html#uploader) of a package on
-[pub.dartlang.org](http://pub.dartlang.org) to add or remove other uploaders for
-that package. It has two sub-commands, `add` and `remove`, that take the email
-address of the person to add/remove as an uploader. For example:
-
-    ~/code/transmogrify$ pub uploader add nweiz@google.com
-    'nweiz@google.com' added as an uploader for package 'transmogrify'.
-
-    ~/code/transmogrify$ pub uploader remove nweiz@google.com
-    'nweiz@google.com' is no longer an uploader for package 'transmogrify'.
-
-If a package has only one uploader, that uploader can't be removed. You may
-remove yourself as an uploader (as long as there are other uploaders), but you
-won't be able to re-add yourself again afterwards.
-
-By default, the package in the current working directory will have its
-uploaders modified. You can also pass the `--package` flag to choose a
-package by name. For example:
-
-    $ pub uploader --package=transmogrify add nweiz@google.com
-    'nweiz@google.com' added as an uploader for package 'transmogrify'.
-
-Note that uploaders are identified by their Google accounts, so use a Gmail or
-Google Apps email address for any new uploaders.