Add deploy guide.

DEPLOY.md

@@ -0,0 +1,67 @@
+# Deploying Libraries
+
+Getting your library into [Clojars](http://clojars.org) is fairly
+straightforward as is documented near the end of
+[the Leiningen tutorial](https://github.com/technomancy/leiningen/blob/stable/TUTORIAL.md).
+However, deploying is not always as straightforward as the process
+described there.
+
+## Clojars Forks
+
+Sometimes you'll need to publish libraries that you don't directly
+maintain, either because the original maintainer hasn't published it
+or because you need some bugfixes that haven't been applied upstream
+yet. Don't do this if it's at all possible to get the upstream project
+to release a snapshot somewhere with the changes you need, but in some
+cases it's unavoidable.
+
+In this case you don't want to publish it under its original group-id,
+since either you won't have permission to do so (if it's already on
+Clojars) or it will conflict with the same artifact on other
+repositories. You should use "org.clojars.$USERNAME" as the group-id
+instead.
+
+## Private Repositories
+
+There may be times when you want to make a library available to your
+team without making it public. This is best done by setting up a
+private Maven repository. Both [Archiva](http://archiva.apache.org/)
+and [Nexus](http://nexus.sonatype.org/) will allow you to set up
+private, password-protected repositories. These also provide proxying
+to other repositories, so you can set <tt>:omit-default-repositories</tt>
+in project.clj, and dependency downloads will speed up by quite a bit
+with only one server to check.
+
+The private server will need to be added to the <tt>:repositories</tt>
+listing in project.clj. Archiva and Nexus offer separate repositories
+for snapshots and releases, so you'll want two entries for them:
+
+    :repositories {"snapshots" {:url "http://blueant.com/archiva/snapshots"
+                                :username "milgrim" :password "locative.1"}
+                   "releases" "http://blueant.com/archiva/internal"}
+
+Private repositories need authentication credentials. You'll need to
+provide either a <tt>:username</tt>/<tt>:password</tt> combination or
+a <tt>:private-key</tt> location with or without a
+<tt>:passphrase</tt>. If you want to avoid putting sensitive
+information into your project.clj file as in the <tt>releases</tt>
+entry above, you can store authentication information in
+<tt>~/.lein/init.clj</tt> as a <tt>leiningen-auth</tt> map keyed off
+the repository's URL:
+
+    (def leiningen-auth {"http://localhost:8080/archiva/repository/internal/"
+                         {:username "milgrim" :password "locative.2"}})
+
+This also allows different users using the same checkout to upload
+using different credentials.
+
+Once you've set up a private repository and configured project.clj
+appropriately, you can deploy to it:
+
+    $ lein deploy
+
+If the project's current version is a SNAPSHOT, it will deploy to the
+<tt>snapshots</tt> repository; otherwise it will go to
+<tt>releases</tt>. The <tt>deploy</tt> task also takes a repository
+name as an argument that will be looked up in the
+<tt>:repositories</tt> map if you want to override this.