Organise output, put examples into their groups.

This change helps the pollution hunter to:

* read at-a-glance the file name of the example/group
* re-order groups (large chunks of a suite) before examples (smaller
  chunks)

Interestings:

* modelled a suite's Run
* add some groups/examples to example spec
* replace stub with custom config double
* write file after suite, instead of every time ordering block is called
* use a presenter to display each item
* separate files for each class, == operator for List