Newsdownloader: add HTTPS support and fixes
Newsdownloader: add HTTPS support and fixes

* Fixes #3041 (HTTPS)
* Fixes unlimited (limit = 0) was broken
* Fixes titles and links with attributes

poire-z/koreader,houqp/koreader,NiLuJe/koreader,mihailim/koreader,koreader/koreader,Markismus/koreader,lgeek/koreader,NiLuJe/koreader,poire-z/koreader,pazos/koreader,Hzj-jie/koreader,Frenzie/koreader,mwoz123/koreader,Frenzie/koreader,koreader/koreader,apletnev/koreader