On MacOSX, limit the publication of bits to only be the .pkg file from macos109.
On MacOSX, limit the publication of bits to only be the .pkg file
from macos109.

Rider: Fix the hostname trim to cut the bitkeeper.com instead of
       bitmover.com

bk: 55dcb3646c55dRxJO1DJAlI7WoYxCg
bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper,bitkeeper-scm/bitkeeper