Many cbz and cbr out there are incorrectly named. for
example book.cbz is accidentally named book.cbr.
In this case, comical will refuse to open the file
until we rename the file. This is tedious. (It'd be
fine if there were only a handful of misnamed file but
is a pain if there's a lot)
Anyway, I did a patch whereby if one file type fails,
it will retry with the other file type. Only if both
zip and rar fails will it issue the error message.
Patch is in the file attached.