Add support for downloading to internal storage and fix project build.

- Update outdated library com.github.QuadFlask:colorpicker in build.gradle
- Update SettingsActivity with option to select download directory.
- Add migration in PreferenceUtil to support download location storage.
- Update MusicUtil to look for user-provided location when building locations.
- Update DownloadService to download to specified location.

app/src/main/res/values/strings.xml

@@ -107,6 +107,7 @@
     <string name="pref_header_library">Library</string>
     <string name="pref_header_lock_screen">Lock Screen</string>
     <string name="pref_header_notification">Notification</string>
+    <string name="pref_header_storage">Storage</string>
 
     <string name="pref_title_direct_play_codecs">Direct Play Codecs</string>
     <string name="pref_title_categories">Categories</string>
@@ -143,6 +144,9 @@
     <string name="pref_summary_categories">Configure visibility and order of display categories.</string>
     <string name="pref_summary_direct_play_codecs">Disable direct play codecs to force transcoding.</string>
     <string name="pref_summary_gain_adjustment">Adjust the gain of the music player\'s output</string>
+    <string name="save_lyrics">Save Lyrics</string>
+    <string name="cached_songs_location">Cached Songs Location</string>
+    <string name="cached_songs_location_summary">Select where to store cached songs</string>
 
     <string name="delete_action">Delete</string>
     <string name="remove_action">Remove</string>

app/src/main/res/xml/pref_cache.xml

@@ -4,7 +4,7 @@
 
     <com.dkanada.gramophone.views.settings.JellyPreferenceCategory android:title="@string/pref_header_cache">
 
-        <com.dkanada.gramophone.views.settings.FilePreference
+        <Preference
             app:iconSpaceReserved="false"
             android:key="location_download"
             android:title="@string/pref_title_download_location" />

app/src/main/res/xml/pref_storage.xml

@@ -0,0 +1,11 @@
+<?xml version="1.0" encoding="utf-8"?>
+<androidx.preference.PreferenceScreen xmlns:app="http://schemas.android.com/apk/res-auto">
+    <SwitchPreference
+        app:key="save_lyrics"
+        app:title="@string/save_lyrics"
+        app:defaultValue="false" />
+    <Preference
+        app:key="cached_songs_location"
+        app:title="@string/cached_songs_location"
+        app:summary="@string/cached_songs_location_summary" />
+</androidx.preference.PreferenceScreen>