AGPS: Support basic AGPS configurations by user

Add the following configurations:
 - server host & port
 - network type
 - AGps restart type
 - SUPL server setting

Move the AGPS option definition from Settings.java to
GpsLocationProvider.java (Refer to https://review-android.quicinc.com
/#/c/416122/20/core/java/android/provider/Settings.java)

cherry picked from:
  https://review-android.quicinc.com/#/c/416122/20
  https://review-android.quicinc.com/#/c/522204/3
  https://review-android.quicinc.com/#/c/487777/2

CRs-Fixed: 507969 576143 557234

Change-Id: Ibdfc4fa267e1343d97742fbed6cf8bb35c5efd0a