Add application/postscript to the list of valid tarball content types
Add application/postscript to the list of valid tarball content types

This is required in order to migrate all cookbooks from the Opscode
Community Site.

nellshamrell/supermarket,rafaelmagu/supermarket,robbkidd/supermarket,dpnl87/supermarket,juliandunn/supermarket,nellshamrell/supermarket,chef/supermarket,rafaelmagu/supermarket,dpnl87/supermarket,dpnl87/supermarket,rafaelmagu/supermarket,robbkidd/supermarket,leftathome/supermarket,tas50/supermarket,juliandunn/supermarket,tas50/supermarket,jzohrab/supermarket,leftathome/supermarket,tas50/supermarket,chef/supermarket,leftathome/supermarket,leftathome/supermarket,chef/supermarket,juliandunn/supermarket,jzohrab/supermarket,rafaelmagu/supermarket,robbkidd/supermarket,jzohrab/supermarket,nellshamrell/supermarket,juliandunn/supermarket,tas50/supermarket,chef/supermarket,dpnl87/supermarket,nellshamrell/supermarket,robbkidd/supermarket,jzohrab/supermarket,chef/supermarket