Add password field for WiFi configuration.

1. the certtool.h is modified for avoiding the side effect,
   for saving the configuration with wpa_supplicant.
2. put the loadLibrary back in CertTool.java
3. Fix incorrect JNI declarations.
diff --git a/services/java/com/android/server/WifiService.java b/services/java/com/android/server/WifiService.java
index beadc5f..e2aee42 100644
--- a/services/java/com/android/server/WifiService.java
+++ b/services/java/com/android/server/WifiService.java
@@ -1095,6 +1095,17 @@
                 break setVariables;
             }
 
+            if ((config.password != null) && !WifiNative.setNetworkVariableCommand(
+                    netId,
+                    WifiConfiguration.passwordVarName,
+                    config.password)) {
+                if (DBG) {
+                    Log.d(TAG, config.SSID + ": failed to set password: "+
+                          config.password);
+                }
+                break setVariables;
+            }
+
             if ((config.clientCert != null) && !WifiNative.setNetworkVariableCommand(
                     netId,
                     WifiConfiguration.clientCertVarName,