LB-1442: As blog admin I want to be able to change the SEO related changes

initial commit
LB-1442: SEO settings interface

almost done
LB-1442: SEO settings interface

minor changes
LB-1440: SEO settings interface

final changes
LB-1374
:
Build backend API to handle HTML generation
Merge pull request #620 from ioanpocol/liveblog16

LB-1374
Merge pull request #619 from nidzix/liveblog16

LB-1454 : Change css of Rheinische Post live blog theme
LB-1448: Please update Tageswoche demo and production instance to 1.6, install new themes based on zeit and zeit_solo

Added themes.
Merge pull request #621 from nistormihai/liveblog16_clean

LB-1448: Please update Tageswoche demo and production instance to 1.6, i...
Merge pull request #618 from vladnicoara/liveblog16-seo

LB-1442: SEO settings interface
LB-1454 : Change css of Rheinische Post live blog theme

Update RP embed theme to follow latest requests