Fix database definition errors in MySQL

Hello,

I was attempting to run the Flowers application and ran into some trouble initialising the database.

The first commit fixes errors like this:
``ERROR 1101 (42000) at line 49: BLOB/TEXT column 'type' can't have a default value``
when importing the *sql/Interchange6-Schema-0.013-MySQL.sql* file into MySQL 5.6.15;

The second commit fixes ``Flowers/bin/populate`` errors like this:
```DBIx::Class::Storage::DBI::_dbh_execute_for_fetch(): execute_for_fetch() aborted with 'Field 'created' doesn't have a default value' at populate slice:
{
  canonical_sku => undef,
  description => "Surprise the one who makes you smile, or express yourself perfectly with this stunning...```