Makes db thread-safe

It was needed for simplicity and various optimization

album_database_test.go

@@ -17,7 +17,9 @@ var _ = Suite(&AlbumDatabaseSuite{})
 func (s *AlbumDatabaseSuite) SetUpSuite(c *C) {
 	s.db = OpenAlbumDatabase(filepath.Join(c.MkDir(), "satdb.bar.satellite/db"))
 	for _, a := range albumsDataTest {
-		c.Assert(s.db.AddOrUpdate(&a), IsNil)
+		//we need to copy the value to avoid aliasing
+		aCopied := a
+		c.Assert(s.db.AddOrUpdate(&aCopied), IsNil)
 	}
 }
 
@@ -31,7 +33,6 @@ func (s *AlbumDatabaseSuite) TestCanDelete(c *C) {
 }
 
 func (s *AlbumDatabaseSuite) TestCanGet(c *C) {
-
 	for _, a := range albumsDataTest {
 		fromDb, err := s.db.Get(a.ID)
 		if c.Check(err, IsNil) == true {
@@ -41,7 +42,6 @@ func (s *AlbumDatabaseSuite) TestCanGet(c *C) {
 }
 
 func (s *AlbumDatabaseSuite) TestCanSort(c *C) {
-	// here
 	start := time.Now()
 	data := []AlbumID{160366, 58595, 15875, 9935, 84448, 46005, 19762, 164, 52100, 8179, 44989, 32043, 22737, 754}
 	sorted, err := s.db.ByPurchaseDate()