Implement initial audiobook UX (some of which is a bit of a WIP).

- Renamed various components and moved them to src/components.
- Renamed KOTO_PREFERRED_MODEL* to KOTO_PREFERRED_PLAYLIST*
- Renamed koto string utility functions to always be prefixed with koto_utils_string_ for consistency.
- Added configuration options for show / hiding various album information, as well as preferred sort type.
- Changed db schema to reflect various metadata changes (sorry).
- Implemented genre, narrator, year aggregation from KotoTrack to KotoAlbum for use in KotoAlbumInfo and audiobooks.
- Rearchitected our playlist functionality for KotoAlbums to always have an inner KotoPlaylist that is used.
- Added various getters / setters for new koto_album functionality.
- Implement aggregation of KotoAlbum pointer aggregation in the KotoArtist as a GQueue and GListStore instead of GList so we can get all the albums associated with an artist and use the GListStore for the audiobook view.
- Implement some initial album sorting in Artists (more work to do on this front).
- Many improvements to file indexing logic for CD and position detection, various new koto_track_helpers.
- Add new logic for knowing when to hide playlists given we generate them for each Album now.
- Fix missing updates of KotoPlaylist in KotoNav.
- Added playback position to KotoPlayerbar, renamed bar refs to self.
- New Playlist state saving.
- Updated track ticking logic for track in KotoPlaybackEngine.
- Fixed playback position detection in our KotoPlaybackEngine by swapping from GST_FORMAT_DEFAULT to GST_FORMAT_TIME.
- Changed our get_progress to divide by GST_SECOND.
- Fixed missing type checks in various KotoPlaybackEngine functions.

Fixes #13. Fixes #14. Fixes #15.

theme/pages/_audiobook-library.scss

@@ -0,0 +1,36 @@
+// This file contains the styling for our Audiobook Library
+
+@import '../vars';
+
+.audiobook-library { // Library page
+	.genres-banner { // Banner for genres list
+		.large-banner { // Large banner with art for each genre
+			padding: $itempadding;
+
+			.audiobook-genre-button { // Genre buttons
+				.koto-button {
+					font-size: 2em;
+					margin: 0.5em;
+				}
+			}
+		}
+	}
+
+	.writers-button-flow { // Flowbox of buttons for writers
+		padding: 0 $itempadding; // Horizontal padding of our standard item padding
+
+		flowboxchild {
+			padding: 0;
+
+			&:nth-child(even) {
+				margin: 0 0.5em;
+			}
+
+			.writer-button { // Writer button
+				color: $text-color-bright;
+				font-size: 1.4em;
+				background-color: $bg-secondary;
+			}
+		}
+	}
+}

theme/pages/_music-local.scss

@@ -21,14 +21,6 @@
 						& > overlay {
 							margin-right: $itempadding;
 						}
-
-						& > box {
-							& > label {
-								font-size: xx-large;
-								font-weight: 900;
-								padding: $halvedpadding 0;
-							}
-						}
 					}
 				}
 			}