Set umask

Ensure we have a known-good umask.  Otherwise files such as
/etc/polkit-1/rules.d/50-libvirt-$STACK_USER.rules may not be readable
by non-root users afterwards.

Also reworded some comments to be more clear.

Change-Id: I7653d4eee062cf32df22aa158da6269b1aa9a558
Closes-Bug: #1265195
Implements fix to run lbaas service on fedora with devstack

changes 'user_group = nobody' in 'haproxy' section of lbaas_agent.ini

Change-Id: I801fec5a11d8abd97cb6f5cdff35fabb9eaf9000
Closes-Bug: 1283064
Fix libvirt polkit settings

After the https://review.openstack.org/#/c/75314 merged
the /etc/polkit-1/rules.d/50-libvirt-stack.rules files contains
subject.user == '"stack"' instead of
subject.user == 'stack'.

Change-Id: I09f252b2d0e53f012facb9f7eaa21c1e1bdf492b
Fix exit_trap() error if no child processes

Bug-Id: 1285776
Change-Id: Iad7a9f2c03cc39159beda55345f232cefed10520
Stop trying to create the 'ironic' user twice

After 09bd7c8fd5a6 landed, a conflict between lib/ironic and
extras.d/50-ironic.sh was exposed, breaking Ironic's check and gate
tests.

This resolves that conflict by only creating the 'ironic' user once.

Change-Id: Ic41517f0977c84a82f92f58565aaee6b5cc7eb3e
Merge "Implements fix to run lbaas service on fedora with devstack"
Merge "Fix libvirt polkit settings"
Merge "Set umask"
Merge "Fix exit_trap() error if no child processes"
Merge "Stop trying to create the 'ironic' user twice"
Merge branch 'master' of github.com:openstack-dev/devstack