#10 should wait to do compression until all files are added

[Kenny Pearce]

in the present version of fileroller (2.4.4) as soon as
a file is added the archive is decompressed and
recompressed. This makes adding multiple files to an
already large archive extremely difficult, and actually
eliminates most of the benefits of using a GUI, since
you can't select all of your files one by one with a
dialog and then compress all at once.