(maint) Stub out puppet master puts

On Ruby 1.9.3, stubbing `$stdout.puts` will stub out calls to `puts` but
on 1.8.7 this stubbing fails. This commit updates the tests to stub out
the `puts` method on the master object to catch and silence the catalog
outputting in the tests on 1.8.7.
Merge branch 'maint-stub_master_compile_puts'