support more arguments to diff

[Eitan Adler <lists@xxxxxxxxxxxxxx>]

This patch isn't perfect since {Net,DragonFly,Open,Free}BSD are not
identical but this patch at leasts makes the completion a lot closer
to reality.

Currently FreeBSD doesn't even show -q for example.

diff --git i/Completion/Unix/Type/_diff_options
w/Completion/Unix/Type/_diff_options
index 55ddecd2a..e436d5cfe 100644
--- i/Completion/Unix/Type/_diff_options
+++ w/Completion/Unix/Type/_diff_options
@@ -148,7 +148,7 @@ else
         '-S+[set first file in comparison]:start with file:_files'
       )
     ;;
-    openbsd*)
+    dragonfly*|freebsd*|netbsd*|openbsd*)
       of+=' -n -q -u -C -D -U'
       args=(
         "($of)-n[produce an rcsdiff(1)-compatible diff]"

-- 
Eitan Adler