LB-1801: Ruhrnachrichten blog sometimes not loading on IE 9/10

Also fixed pretty date issues.
Added new i18n strings for pretty date.
Merge pull request #748 from nistormihai/master

LB-1801: Ruhrnachrichten blog sometimes not loading on IE 9/10
LB-1805: Localisation improvements for pretty date (Ruhrnachrichten)

Issues with parsing some elements.
Merge pull request #749 from nistormihai/master

LB-1805: Localisation improvements for pretty date (Ruhrnachrichten)
LB-1805: Localisation improvements for pretty date (Ruhrnachrichten)

More then 4 weeks bug.
Merge pull request #750 from nistormihai/master

LB-1805: Localisation improvements for pretty date (Ruhrnachrichten)
Merge pull request #747 from nidzix/master

LB-1807: Bold font not displayed correctly on NZZ Live Blogs (desktop only!)
NZZ mobile theme update