Add EAP/802.1X configuration for WiFi Setting.

1. Remove the isEnterprise() filter in Scanresult.
2. This requires the new fields such as identity, eap, certificate/key
to support EAP authentication in Wifi Settings.
3. Add simple file-based keystore to select the cert/key from UI.

-- Updated from the comments.
-- Fix the bug for passing null pointer for adding spinner items.

src/com/android/settings/wifi/WifiLayer.java

@@ -1133,7 +1133,6 @@ public class WifiLayer {
                      * Hidden networks show up with empty SSID.
                      */
                     if (AccessPointState.isAdhoc(scanResult)
-                            || AccessPointState.isEnterprise(scanResult)
                             || TextUtils.isEmpty(scanResult.SSID)) {
                         continue;
                     }