Refactor containers and library loading

Replace trackPtr with raw Track* pointers in HashTable, add loadLibrary
to PlayerLocal, remove unused File helpers, and fix broken artwork/artist
SQL bindings.

src/PlayerLocal.cpp

@@ -4,6 +4,8 @@
 #include "../include/Database.h"
 #include "../include/Containers.h"
 
+#include <memory>
+
 using db = Database;
 
 void Player::play () { PE_.startPlayback(); }
@@ -55,3 +57,12 @@ void PlayerLocal::scanLibrary(){
         db_.addTrack( t );
     }
 }
+
+void PlayerLocal::loadLibrary() {
+    db_.fetchAll( library );
+    for ( auto t : library ) {
+        tracks_.ht_insert(t.title.toCString(), &t );
+        artists_.ht_insert( t.artist.toCString(), &t );
+        albums_.ht_insert( t.album.toCString(), &t );
+    }
+}