Update translation loading

[kraftbj]

Function _load_textdomain_just_in_time was called incorrectly. Translation loading for the secure-custom-fields domain was triggered too early. This is usually an indicator for some code in the plugin or theme running too early. Translations should be loaded at the init action or later. (This message was added in version 6.7.0.)

A doing_it_wrong thrown in the initialize() method.

[dsplz]

How did you fixed that?

[kraftbj]

@dsplz Delayed translating until later, see #47

Originally, __() was called very early. Now, it defaults to a hardcoded version and __() runs to override it later.