VolumeZen: Sound & Notifications settings.

- Add sound settings under the newly combined Sound & Notifications
  top-level settings page.
- New slider preferences for setting audio stream volumes.
- Migrate checkbox prefs to switch prefs.
- New settings subpage for touch sounds.
- New settings subpage for "Showing notifications"
- New setting pref for displaying intercepted notifications in zen mode.
- New tri-state lockscreen notifications pref.
- Add priority + sensitivity options to app notification dialog.
- Remove badges on app notifications row, migrate to subtitle text.
- Migrate strings to common spot in strings.xml
- Remove heads up setting.
- Remove tweaks category (unused).
- Clean up notification settings, separate out into a code section per option.
- Clean up _settings.xml files, prefix each pref with option name.
- Add appropriate indexing data to each settings page.

Depends on f/b change Ic30aa575ae07650cee62c8c1d83b6bc69395cf0d

Change-Id: If700385a7d0057f6c4c4bcf6e648dcf88b8ebff2

src/com/android/settings/notification/ZenModeSettings.java

@@ -329,7 +329,7 @@ public class ZenModeSettings extends SettingsPreferenceFragment implements Index
             if (automatic == null || automatic.length == 0) {
                 return null;
             }
-            final String divider = getString(R.string.zen_mode_entry_conditions_summary_divider);
+            final String divider = getString(R.string.summary_divider_text);
             final StringBuilder sb = new StringBuilder();
             for (int i = 0; i < automatic.length; i++) {
                 if (i > 0) sb.append(divider);