Log Message:
Update to 1.71

Upstream changes:
2016-01-08   Karen Etheridge <ether@cpan.org>

  Release 1.71

    No changes since 1.70_001

2015-12-29   Karen Etheridge <ether@cpan.org>

  Release 1.70_001

  Kaitlyn Parkhurst:

    - Localize $@ when attempting to load URI subclasses (PR#30)

  Karen Etheridge:

    - speed up construction time by not attempting to load the same
      non-existent URI subclass twice