blackhole zip file support

[jarvis2323]

pairofdimes reminded me of this when I was looking that the bug reports posts... anyway for us cheapskates without newzbin.com accounts, its not uncommon for nzb files to be in a zip file.  Would be nice if blackhole directory supported both nzb and zip files.

[switch]

Place a zip file in your blackhole folder. It will add any nzb's it finds inside.

Make sure however that no zip's that do not contain any nzb's are put inside the blackhole as until it is fixed you will experience problems.

[shypike]

Will be implemented in 0.3.1, along with nzb.gz support and skipping of zip files that do not contain nzb's.
Spec:
.nzb : processed if true NZB or a gzipped one with a nzb extension (happens with IE sometimes)
.nzb.zip or .zip : processed only if containing nothing but NZB file(s)
.nzb.gz : processed
all other files: skipped