Improve shareText and title

[InfoLibre]

1. Show the platform name on the button (shareText) like with https://elfsight.com/fr/social-media-share-buttons/, http://robindesbancs.fr/elements/pro-elements/share-buttons/, https://socialsharingplugin.com/, https://jetpack.com/support/sharing/, etc. English fallback?
2. Improve title.

[richard67]

This change here makes sense when you have a title like e.g. "Share this page" and then show the sharing icons close to that.

On the other hand, if you don't have such a title or label and have also buttons with social media icons to go to the home page in the particular social media, then it would be confusing, and the current sharing texts and titles are more clear.

So maybe it would be good to have a configuration option like e.g. "use_brand_name" or so, to toggle between the current behaviour and the one introduced by this PR?

[InfoLibre]

People know that these icons are for sharing and and a title near these buttons usually indicates this. But I agree, a configuration option to choose between use_brand_name and current behavior is a good idea. It's not always a brand, it can be different for some icons: email, RSS, print. I think it's more about the communication medium.