Raise error when identifiers are not unique
Remove debug statement
Merge pull request #435 from nanoc/unique-identifiers

Raise error when identifiers are not unique
Merge branch 'release-3.6.x'

Conflicts:
	lib/nanoc/base/source_data/site.rb
Add identical identifiers release note
Bump version to 3.6.10
Set release date for 3.6.10
Update Gemfile.lock
Add release notes for 3.6.10.1
Bump version to 3.6.10.1
Merge branch 'release-3.6.x'

Conflicts:
	Gemfile.lock
	NEWS.md
	lib/nanoc/version.rb
Update copyright year to 2014

A bit late, I guess! We’re well in 2014 now.
Update Gemfile.lock
Merge branch 'release-3.6.x'

Conflicts:
	Gemfile.lock
Merge branch 'master' into old-4.x

Conflicts:
	Gemfile.lock
	lib/nanoc/base/errors.rb
	test/base/test_site.rb