Bug 573064: Support full clear - extended "E3" capability

Change-Id: I9d4f7fffb11cc5386eb0a4e5c0445f1fc518b0a5

Author: jonahgraham

terminal/plugins/org.eclipse.tm.terminal.control/src/org/eclipse/tm/internal/terminal/emulator/VT100Emulator.java

@@ -784,6 +784,11 @@ private void processAnsiCommand_J() {
 			text.eraseAll();
 			break;
 
+		case 3:
+			// Erase display and clear scrollback (extended "E3" capability)
+			text.clearAll();
+			break;
+
 		default:
 			Logger.log("Unexpected J-command parameter: " + ansiParameter); //$NON-NLS-1$
 			break;