This filter, in the main window, shows only the manga that still need
to be collected, not the completed ones.
* src/data.c (data_get_manga): Use `data_get_manga_for_query'.
(data_get_incomplete_manga): New function, get all manga that arent'
completely collected yet.
(data_get_manga_for_query): New function, fetches all the manga as
`query' specifies.
* src/data.h: Add `data_get_incomplete_manga'.
* src/eom-main-window.c (filter_args): New struct. Contains arguments
needed by the filter callback.
(eom_main_window_load): Accept a list of manga, this list will be
used to show the manga, if it's NULL, a list of all manga is used.
(eom_main_window_add_menu): Add `All' and `Collect' filter buttons.
(eom_main_window_on_filter): Callback for the filter buttons,
reloads the list with the correct manga.
* src/eom-main-window.h: Add manga parameter to
`eom_main_window_load'.
* src/interface.c (interface_show_main_window): Pass `NULL' to
`eom_main_window_load' to show all manga.
