Add connector param to array_to_sentence_string filter

[thetimbanks]

When building a sentence based off an array, the default connector is "and". This will allow other terms to be used such as "or".

[pathawks]

Seems reasonable. We just need to document this change.

[thetimbanks]

Is that something I need to add to one of the markdown documents?

[pathawks]

@thetimbanks Yup. The documentation for our filters is in /docs/_docs/templates.md. You will need to update the section describing array_to_sentence_string to explain the new parameter. 👍

[thetimbanks]

I amended the documentation change in to the commit.

[pathawks]

/cc @jekyll/ecosystem?

[benbalter]

@jekyllbot: merge +minor

[benbalter]

Thanks @thetimbanks! 🦃 🌮 🎉

[thetimbanks]

🦃 👍 Thanks!