pixz: new package

Add a package for pixz (pronounced pixie), a parallel, indexing version of
xz.

See https://github.com/vasi/pixz

Signed-off-by: Vincent Stehlé <vincent.stehle@laposte.net>
Acked-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Tested-by: Arnout Vandecappelle (Essensium/Mind) <arnout@mind.be>
Signed-off-by: Thomas Petazzoni <thomas.petazzoni@free-electrons.com>
diff --git a/package/Config.in b/package/Config.in
index a811ff6..36747a2 100644
--- a/package/Config.in
+++ b/package/Config.in
@@ -64,6 +64,7 @@
 	source "package/lzip/Config.in"
 	source "package/lzop/Config.in"
 	source "package/p7zip/Config.in"
+	source "package/pixz/Config.in"
 	source "package/unrar/Config.in"
 	source "package/unzip/Config.in"
 	source "package/xz/Config.in"