Change skeleton to provoke RSpec "duplicate declaration" error

Duplicate declaration: Class[Skeleton] is already declared; cannot redeclare at
/Users/mlafeldt/devel/jimdo/puppet-skeleton/fixtures/manifests/site.pp:3
Move test/site.pp to test/integration/site.pp
Give rspec-puppet the empty site.pp it requires
Merge pull request #3 from mlafeldt/fix-rspec-fixtures

Fix RSpec fixtures