Append home page title to / title (if on home)

[rmacd]

Currently the site home page uses "site title" only in the <title> tag

All other pages use format <title>page_title - site_title</title>.

For "home page" in search engine, it would be good to be able to provide a "site tagline" on the home page only.

This change will therefore allow the title to be appended on the site home page, ie <title>site_title - homepage_title</title>.

To do this, the file content/_index.md need simply include title: element as usual: if present, this will be appended to page title of home page.

[ghost]

@rmacd Is this why bing and google tell me I have no H1 tag or something else? I'm not terribly familiar with hugo yet. Do you know how I can fix it? Do I need to wait for this?