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/keystore/jni/certtool.c b/keystore/jni/certtool.c
index c2a137e..fabf5cd 100644
--- a/keystore/jni/certtool.c
+++ b/keystore/jni/certtool.c
@@ -115,9 +115,9 @@
     /* name, signature, funcPtr */
     {"generateCertificateRequest", "(ILjava/lang/String;)Ljava/lang/String;",
         (void*)android_security_CertTool_generateCertificateRequest},
-    {"isPkcs12Keystore", "(B[)I",
+    {"isPkcs12Keystore", "([B)Z",
         (void*)android_security_CertTool_isPkcs12Keystore},
-    {"generateX509Certificate", "(B[)I",
+    {"generateX509Certificate", "([B)I",
         (void*)android_security_CertTool_generateX509Certificate},
     {"isCaCertificate", "(I)Z",
         (void*)android_security_CertTool_isCaCertificate},