refs #16031 [fid_adlr] add basic content for home page

* add basic structure for home page
* add de / en translations for home page texts
* import rss feed => todo: mv to myresearch controller
* fix some css bugs: remove transitions
* fix basic styling for xl screens
** keep home text centered
* fix display menu toggle for edge
** problem with transitions still exists - need to disable collaps-timing
* set z-index for header-links
* fix menu z-index for xs
* disable transitions to speed up main menu ecetera
* supplement to home page: xs and sm text sizes
* refactor texts on home page
** transform menu 1 and 2 uppercase
** lower line-height of Blog headline
** databases and new releases in ubuntu mono
** services sub headlines in ubuntu mono / separate div
* fix font color and offsets in headlines
* refactor blog import
** extract url data strings to main config
** rough catching of exceptions in rss helper
** set fallback = direct link to blog
* fix line-height of services headlines for md screen - use same as lg