Log Message:
Update p5-Date-Manip to 6.51:

=head1 VERSION 6.51  2015-09-01

Changes suggested by perlcritic

Played with perlcritic and made a few minor changes based on it's suggestions.
I doubt I will use perlcritic significantly.

Date::Manip::Delta::value now returns an empty string

If a delta has an error, or no valid delta in it, the value method returns
an empty string instead of undef.  This is to be consistent with the
Date::Manip::Date::value method which returns an empty string.

Bug fixes

Fixed a bug where date/delta calculations with deltas that are too
large was not working correctly.  They now set an error condition
and fail.  RT 105737

Fixed a bug introduced by the previous patch and luckily discovered
pre-release by Tom Wyant.

Fixed code that produced a warning in 5.22.0.  Tom Wyant

Improved DM6 ParseDate and ParseDateString

Added C<@opts> argument.  Based on RT 105622.

Time zone fixes

Newest zoneinfo data (tzdata 2015f)

Now uses /etc/localtime as a method to determine the local timezone.
Patch supplied in RT 105159 (modified by me).  The patch uses some
code derived from DateTime::TimeZone .

Clearer message when the date is not valid in the timezone.

Test fixes

Added a number of new tests based on Devel::Cover.  Over the next several
releases, I intend to continue to add tests until coverage is 100%.

Documentation fixes

Fixed a typo.  RT 105546