[meta] revisit social media integration

[pkra]

For moving from beta to www, we need to

• redirect dlvr.it to pipe in the feeds from the new site
• look into doing RT's (does ifttt still work for that?) instead of RSS feeds for editors' picks

[pkra]

Twitter and facebook will be done via https://github.com/mathblogging/mathblogging-base/issues/52