Update Mac OS X Installer.app description bundle, so that the ngIRCd
package can only be installed on the root volume ("/"); and make sure
that all installed files and directories have correct ownership and
permissions.
This patch adds a new make target, "osxpkg", to the main Makefile which
gereates a Apple Mac OS X installer package of ngIRCd. The packagemaker(1)
project bundle is stored in contrib/MacOSX/ngIRCd.pmdoc.
