wait up to 5 seconds for the headless firefox to die(sounds creepy when I say it like that)

Former-commit-id: 800de73b9d
Former-commit-id: 7367d274c1a7d06bf358102ee89e1aa00049fbd1

src/java/net/i2p/i2pfirefox/I2PBrowser.java

@@ -196,6 +196,9 @@ public class I2PBrowser extends I2PCommonBrowser {
           if (arg.equals("-usability")) {
             i2pBrowser.usability = true;
           }
+          if (arg.equals("-noproxycheck")) {
+            i2pBrowser.setProxyTimeoutTime(0);
+          }
           if (!arg.startsWith("-")) {
             visitURL.add(ValidURL(arg));
           }