added proxy documentation

docs/setup/README.md

@@ -4,6 +4,7 @@
     * [Plugins](plugins.md)
 * Server
     * [Server](server.md)
+    * [Proxy](proxy.md)
     * [Nginx](nginx.md)
 * Remotes
     * [GitHub](github.md)

docs/setup/nginx.md

@@ -1,6 +1,6 @@
 # Nginx
 
-Using a proxy server is **not necessary**. Drone serves most static content from a CDN and uses the Go standard library’s high-performance net/http package to serve dynamic content.
+Using a proxy server is **not necessary**. Drone serves most static content from a CDN and uses the Go standard library's high-performance net/http package to serve dynamic content.
 
 If using Nginx to proxy traffic to Drone, please ensure you have version 1.3.13 or greater. You also need to configure nginx to write `X-Forwarded_*` headers:
 

docs/setup/proxy.md

@@ -0,0 +1,31 @@
+# Proxy
+
+This document provides high-level instructions for configuring Drone to work with a corporate proxy server.
+
+## Http Proxy
+
+The HTTP_PROXY environment variable holds the hostname or IP address of your proxy server. You can specify the HTTP_PROXY variables in your `/etc/drone/dronerc` file or as an envronment variable.
+
+```
+HTTPS_PROXY=https://proxy.example.com
+HTTP_PROXY=http://proxy.example.com
+```
+
+These variables are propogated throughout your build environment, including build and plugin containers. To verify the environment variables are being set in your build container you can add the `env` command to your build script.
+
+We also recommend you provide both uppercase and lowercase environment variables. We've found that certain common unix tools are case-sensitive:
+
+```
+HTTP_PROXY=http://proxy.example.com
+http_proxy=http://proxy.example.com
+```
+
+## No Proxy
+
+The `NO_PROXY` variable should contain a comma-separated list of domain extensions the proxy should not be used for. This typically includes resources inside your network, such as your GitHub Enterprise server.
+
+```
+NO_PROXY=.example.com, *.docker.example.com
+```
+
+You may also need to add your Docker daemon hostnames to the above list.

docs/setup/upgrade.md

@@ -1,5 +1,7 @@
 # Upgrading
 
+> Warning. There is no automated migration from 0.3 to 0.4 due to substantial changes in database structure.
+
 Drone is built continuously, with updates available daily. In order to upgrade Drone you must first stop and remove your running Drone instance:
 
 ```
@@ -13,7 +15,7 @@ Pull the latest Drone image:
 sudo docker pull drone/drone:0.4
 ```
 
-Run the container using the latest Drone image:
+Re-run the container using the latest Drone image:
 
 ```
 sudo docker run \