General development: While there is Makefile.PL/EU::MM support within the
distribution, a lot of the authoring stuff depends upon Build.PL/M::B, in
particular, running author tests.

Naming standard: Things that are distribution-private (as opposed to
class/package-private) begin with double underscore.

Steps for adding a new Policy:

 * Create tests in t/[category]/[name].run
 * Create the .pm in lib/Perl/Critic/Policy/[category]/[name].pm
 * If it applies_to() PPI::Document, perhaps add an exception in
   t/03_pragmas.t
 * Mention it in Changes
 * svn add t/[category]/[name].run lib/Perl/Critic/Policy/[category]/[name].pm
 * tools/svnkeywords t/[category]/[name].run lib/Perl/Critic/Policy/[category]/[name].pm

 * Remove from TODO
 * After release, set co-maint in PAUSE