Remove deprecated usage of GtkAlignment in details dialog.

Also, make the dialog slightly bigger (wider).
Remove deprecated usage of GtkAlignment in settings dialog.
Remove deprecated usage of GtkAlignment from "Add tags" dialog.

Also, make it resizable so the user can easily enter more tags if needed.
Remove deprecated usage of gtk_misc_set_padding in the authorization dialog.
Add accelerator for Settings dialog: Ctrl+P
Adjusted margins and paddings in settings dialog
Adjusted margins and paddings in 'Edit details' dialog
Adjusted margins and paddings in 'Add to group|set' dialogs