LB-1839: Merge master branch to devel

Fixed merging issues not signaled by git. ( due to the mixed CRLF vs LF)
Merge commit '009bb83229232469ba5aab6282070ccfe15afad5' into devel-merge
Squashed 'plugins/embed/' changes from 02e244d..24db177

24db177 Merge pull request #199 from nistormihai/concurrency-fix
4418bac LB-1838: Incorrect timestamps on initial set of SEO/HTML posts
7bb3487 LB-1750: Update tageswoche theme
c178f32 Merge pull request #198 from nidzix/test
5cb7729 Ruhrnachrichten theme fix

git-subtree-dir: plugins/embed
git-subtree-split: 24db177fb47555e92c8f8f5587b016f476f34fa8
Merge pull request #772 from nistormihai/devel-merge

Devel merge
Merge pull request #773 from ioanpocol/devel

Devel
LB-1838: Incorrect timestamps on initial set of SEO/HTML posts

Added missing dependencies.
LB-1838: Incorrect timestamps on initial set of SEO/HTML posts
Added missing dependencies.
LB-1838: Incorrect timestamps on initial set of SEO/HTML posts

Added missing dependencies.
LB-1838: Incorrect timestamps on initial set of SEO/HTML posts
Added missing dependencies.
Merge pull request #774 from nistormihai/devel-merge

Devel merge
Squashed 'plugins/embed/' changes from 24db177..c1c13ef

c1c13ef Merge pull request #200 from nidzix/tageswoche-fix
8e9f6cd Tageswoche css fix

git-subtree-dir: plugins/embed
git-subtree-split: c1c13efc97599cadfbb377b0ebaf89d25e5b7d6b
Merge commit '0a64dd321cae7a1640b65ce656aa61d1a2cf064b' into devel-merge
Merge pull request #775 from nistormihai/devel-merge

Devel merge
LB-1750: Update tageswoche theme

Added missing __init__.py for build tageswoche.
Merge pull request #776 from nistormihai/devel-merge

LB-1750: Update tageswoche theme