Explain how to manually register the wagon for lein2. Fixes #4.

Hopefully we'll have a better solution for this soon.

README.md

@@ -7,22 +7,59 @@ but should be usable in other contexts by deploying to repositories at
 
 ## Usage
 
-### Leiningen
+### Leiningen 2.x
 
 Add the plugin and repositories listing to `project.clj`:
 
 ```clj
 :plugins [[s3-wagon-private "1.1.1"]]
-:repositories {"releases" "s3p://mybucket/releases/"
-               "snapshots" "s3p://mybucket/snapshots/"}
 ```
 
-Versions of Leiningen prior to 1.7.0 don't support `:plugins` in
-project.clj; you will need to install by hand:
+You can store credentials either in an encrypted file or as
+environment variables. For the encrypted file, add this to
+`project.clj`:
 
-    $ lein plugin install s3-wagon-private 1.1.1
+```clj
+:repositories {"private" {:url "s3p://mybucket/releases/" :creds :gpg}}
+```
+
+And in `~/.lein/credentials.clj.gpg`:
+
+```
+{"s3p://mybucket/releases" {:username "AKIA2489AE28488"
+                            :passphrase "98b0b104ca1211e19a6c"}}
+```
 
-You should keep your S3 credentials in `~/.lein/init.clj`:
+The map key here can be either a string for an exact match or a regex
+checked against the repository URL if you have the same credentials
+for multiple repositories.
+
+To use the environment for credentials, include `:creds :env` instead
+of `:creds :gpg` and export `LEIN_USERNAME` and `LEIN_PASSPHRASE`
+environment variables.
+
+See `lein help deploying` for details on storing credentials.
+
+Currently in Leiningen 2 you have to manually activate the plugin with
+the following form at the bottom of project.clj:
+
+```clj
+(cemerick.pomegranate.aether/register-wagon-factory!
+ "s3p" #(eval '(org.springframework.aws.maven.PrivateS3Wagon.)))
+ ```
+
+Future versions should remove the need for this declaration.
+
+### Leiningen 1.x
+
+As above, add the plugin and repositories listing to `project.clj`:
+
+```clj
+:plugins [[s3-wagon-private "1.1.1"]]
+:repositories {"private" {:url "s3p://mybucket/releases/"}}
+```
+
+On 1.x you keep S3 credentials in `~/.lein/init.clj`:
 
 ```clj
 (def leiningen-auth {"s3p://mybucket/releases/"
@@ -33,26 +70,22 @@ You should keep your S3 credentials in `~/.lein/init.clj`:
                       :passphrase "SECRET_KEY"}})
 ```
 
-This will allow you to both read and write to/from S3 buckets as Maven
-repositories. Note that deploying an artifact that doesn't already
-exist will cause an `org.jets3t.service.S3ServiceException` stack
-trace to be emitted; this is a bug in one of the underlying libraries
-but is harmless.
+Note that deploying an artifact that doesn't already exist will cause
+an `org.jets3t.service.S3ServiceException` stack trace to be emitted;
+this is a bug in one of the underlying libraries but is harmless.
 
 If you are running Leiningen in an environment where you don't control
-the user such as Heroku or Jenkins, you can define `leiningen-auth` in
-project.clj after the `defproject` form. However, you should avoid
-committing AWS credentials to your project, so you should take them
-from the environment using `System/getenv`:
+the user such as Heroku or Jenkins, you can include credentials in the
+`:repositories` entry. However, you should avoid committing them to
+your project, so you should take them from the environment using
+`System/getenv`:
 
 ```clj
 (defproject my-project "1.0.0"
   :plugins [[s3-wagon-private "1.1.1"]]
-  :repositories {"releases" "s3p://mybucket/releases/"})
-
-(def leiningen-auth {"s3p://mybucket/releases/"
-                     {:username (System/getenv "AWS_ACCESS_KEY")
-                      :passphrase (System/getenv "SECRET_KEY")}})
+  :repositories {"releases" {:url "s3p://mybucket/releases/"
+                             :username (System/getenv "AWS_ACCESS_KEY")
+                             :passphrase (System/getenv "AWS_SECRET_KEY")}})
 ```
 
 ### Maven