Fix remove_warnings

Method lib/puppet/provider/keystone.rb/self.remove_providers does not
support multi line warnings and client results having more than one
column. This patch is fixing it (not sure how module can work with such
bug before anyway).

Change-Id: I19c3ce68ef786a2641d1e2808cb4db9979bdcfed
Merge "Fix remove_warnings"
Merge git://github.com/puppetlabs/puppetlabs-keystone