Rename various things (consistency Tapas/Tumblr)
Rename various things (consistency Tapas/Tumblr)

As I hope to write a generic class
to handle the logic common to
Tapas and Tumblr, a few things have
been renamed so that the same names
are used in all places.

Also, consistency with the GenericListableComic
class has been improved in places where it
is possible.

SylvainDe/ComicBookMaker