Merge pull request #145 from gcurtis/proxy-docs

Update docs around saving/restoring proxy settings

src/main/java/com/box/sdk/BoxAPIConnection.java

@@ -541,6 +541,10 @@ public void setRequestInterceptor(RequestInterceptor interceptor) {
     /**
      * Saves the state of this connection to a string so that it can be persisted and restored at a later time.
      *
+     * <p>Note that proxy settings aren't automatically saved or restored. This is mainly due to security concerns
+     * around persisting proxy authentication details to the state string. If your connection uses a proxy, you will
+     * have to manually configure it again after restoring the connection.</p>
+     *
      * @see    #restore
      * @return the state of this connection.
      */