Upgrade puppetlabs-haproxy to fix concat module.

install_modules.sh: Upgrade puppetlabs-haproxy to version 0.4.1 to fix
conflicts in the concat module. Old haproxy uses ripienaar's module
other modules want puppetlabs' concat module. This upgrade resolves
that conflict.

Change-Id: Ie036091088a6c325264f8a0b4400dcf601827d50
Merge "Upgrade puppetlabs-haproxy to fix concat module."