create the singleton on first instantiation, not on module import

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
bugfix on tests

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
fetch on MeltedCollection.initialize

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
whitespace

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
bugfix

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
fix previous and next check

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
remove undefined variables from defaults because they may override real values

Signed-off-by: Tomas Neme <lacrymology@gmail.com>
prepend playlist id to media to avoid collisions

Signed-off-by: Tomas Neme <lacrymology@gmail.com>