Make Title Block Dates Translatable

[AWearring]

Updated Published and Updated Date text to be translatable - should have remembered to do this on #154

[ekes]

This is possibly a nit-pick. But maybe someone can find the guidance on this. I think translation should either be:

<span>{{ 'Published'|t }}: </span>{{ published_date }}

But actually more likely

{% trans %}
<span>Published:</span> {{ published_date }}
{% endtrans %}

to make any of the possible variations of translation possible.

[finnlewis]

@AWearring thanks for this, any comment in reply to comment from @ekes above?

[AWearring]

@finnlewis Probably should be <span>{{ 'Published'|t }}: </span>{{ published_date }} taking out the colon makes sense.
This will need to be updated in a lot of places, I suspect

[finnlewis]

Discussing with Merge Tuesday crew, general thinking is that it would be good to follow the suggestion by @ekes above.

{% trans %}
<span>Published:</span> {{ published_date }}
{% endtrans %}

This will allow support for other languages that might want to re-order the structure of the sentence.

[finnlewis]

Note that the translator will then translate the entire string: <span>Published:</span> {{ published_date }}

[AWearring]

@finnlewis @ekes Updated to use {% trans %} as discussed at Merge Tuesday