Remove empty module declaration
Remove empty module declaration

The `PaperTrail::Rails` module will be defined by
`frameworks/rails/controller.rb` and `engine.rb`.
There is no need to define it here.

airblade/paper_trail,ifeelgoods/paper_trail,theRealNG/paper_trail,jnstq/paper_trail,theRealNG/paper_trail,devonestes/paper_trail,ifeelgoods/paper_trail,airblade/paper_trail,jnstq/paper_trail