fallback to site title if page title is not set for og:title tag

[intoeetive]

Fix to avoid trailing | in og:title / twitter:title tags in page title is empty

[benface]

Thank you! I was about to submit exactly the same PR haha.

[benface]

@khalwat Have you seen this?

[khalwat]

Yep, I've seen it. I just need to do some local testing before I can safely merge it as a release.

I've had a few PRs that ended up causing problems, so I try to be conservative about testing them.

[benface]

@khalwat Bump! Hehe