Improvement: do not display an error when the server asked to kill a render

src/com/sheepit/client/Error.java

@@ -32,6 +32,7 @@ public class Error {
 		DOWNLOAD_FILE,
 		CAN_NOT_CREATE_DIRECTORY,
 		NETWORK_ISSUE, RENDERER_CRASHED,
+		RENDERER_KILLED,
 		RENDERER_MISSING_LIBRARIES,
 		FAILED_TO_EXECUTE,
 		UNKNOWN
@@ -122,6 +123,8 @@ public class Error {
 				return "Renderer have crashed. It's mostly due to a bad project or not enough memory. There is nothing you can do about it. Will try an another project in few minutes.";
 			case RENDERER_MISSING_LIBRARIES:
 				return "Failed to launch runderer. Please check if you have necessary libraries installed and if you have enough free place in working directory.";
+			case RENDERER_KILLED:
+			    return "The render stop because either you ask to stop or the server (usually render time too high).";
 			case SESSION_DISABLED:
 				return "The server have disabled your session. It's mostly because your client generate broken frame (gpu not compatible for example).";
 			default: