Require rspec/matchers before require enumerate/integrations/rspec.
Require rspec/matchers before require enumerate/integrations/rspec.

- `if defined?(::RSpec)` it fails to load the enumerize matcher properly when used with rails/spring.
- similar to https://github.com/rails/spring/issues/209

hungrything/enumerize,shaundunne/enumerize,tanraya/enumerize,victor95pc/enumerize,tranvictor/enumerize,quarkstudio/enumerize,brainspec/enumerize,monfresh/enumerize,maurogeorge/enumerize