We don't use Comparable anymore
Flexible postag size in Postag

... and comment about further abstractions mentioned also in #7
Add Reportable#clone
Setup to implement Comparison#report
DRY up cloning off container hashes
Abstract cloning of containers in Reportables
Allow *params for Reportable#replace_with_clone
Add a comment on cloning

... to avoid that I refactor it one day...
Fix formatting in Reportable
Move Reportable#hash_with_clones_values ...

... to HashContainable - we'll need it elsewhere...
Replace report in Sentence when cloned
Whoops, forgot to add replace_with_clone

... too lazy to amend with rebase...
Simplify Reportable#clone

No need for faking an alias_method_chain, just use super!
Replace sentences when a Gold is cloned
Add comment on upcoming work in Comparison#report
Tell, don't ask in Comparison and Reviewable

Move Reviewable#compare logic to Comparison#compare
Tell don't ask in Sentence and Generic

Let the Generic reporter classes collect reports themselves
Make postags more present in report

Count totals of each individual postag and not only the datapoints.
Useful on its own and necessary for diff reports.
Don't include Reportable again in ReportPostags
Add Report::Sentences, subclass of Report::Generic

... as we don't want to calculate unique errors for sentences.