When saving a datetime field, confirm the time is set before using it.

Fixes a critical bug in time support in that the field was always saved because of flawed default behavior.

Fixes #96
Merge pull request #113 from DFMdata/fix-empty-datetime

When saving a datetime field, confirm the time is set before using it.
Load the utilities immediately so themes and plugins can use them
Registering term meta post type on init

See http://codex.wordpress.org/Function_Reference/register_post_type, "register_post_type should only be invoked through the 'init' action."
Merge pull request #116 from alleyinteractive/load-utils-earlier

Load the utilities immediately so themes and plugins can use them