I find that I usually create playlists through either a right click
action or through a keyboard shortcut, so we don't need an extra option
hidden inside a MenuButton. Let's remove the button and show the "Add
Library Path" option directly instead.
Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>
The convention is for gtk builder files named with a ".ui" extension.
Let's rename our file to match, and drop the 6 while we're at it.
Signed-off-by: Anna Schumaker <Anna@NoWheyCreamery.com>