Catch when key is missing on input CSV file

[pabloab]

As said on this StackOverflow answer, Text::CSV::Hashify (v0.08) doesn't take care of uninitialized variables, in particular when user give a key not present on first row of CSV:

Use of uninitialized value $kk in hash element at /usr/local/share/perl/5.22.1/Text/CSV/Hashify.pm line 303, <$IN> line 2.
Use of uninitialized value $kk in hash element at /usr/local/share/perl/5.22.1/Text/CSV/Hashify.pm line 307, <$IN> line 2.
Use of uninitialized value $kk in hash element at /usr/local/share/perl/5.22.1/Text/CSV/Hashify.pm line 309, <$IN> line 2.
Use of uninitialized value $kk in hash element at /usr/local/share/perl/5.22.1/Text/CSV/Hashify.pm line 303, <$IN> line 3.
Use of uninitialized value $kk in concatenation (.) or string at /usr/local/share/perl/5.22.1/Text/CSV/Hashify.pm line 304, <$IN> line 3.

Would be nice to catch the situation and die with a helpful message.

[jkeenan]

Thanks for this report. rt.cpan.org is the preferred issue tracker for my CPAN distributions, so I'm transferring discussion there and closing this github issue.

By my analysis there are two problems: one of code, the other of documentation. They are respectively discussed in:
code: https://rt.cpan.org/Ticket/Display.html?id=125384
and
docs: https://rt.cpan.org/Ticket/Display.html?id=125385

Thank you very much.
Jim Keenan