Add updating section to README

[gkeegan]

This will help cull the number of "how to update?" Issues whenever we need to push out a fix, like how recently NewPipe got completely broken.

This attempts to be an all-inclusive guide to updating NewPipe. If there are any (clean/official) links to additional info, please comment them and I will add it.

Also let me know if this section should be relocated within the README. I figured it would be best to keep it up top, so people see it right away, and then don't make a new Issue.

• I carefully read the contribution guidelines and agree to them.

[theScrabi]

Yea that is ok I guess, ee should put it into te faq as well.

[gkeegan]

@theScrabi I moved the Update section to underneath Coming Features, as I felt that made the Readme flow the best. I also made it linkable.

[TobiGr]

Yea that is ok I guess, ee should put it into te faq as well.

@theScrabi Put it on my list 👍
@gkeegan can you please add a link to #1981 which resolves the problem with different signing keys? @theScrabi Is there a way other people except you and theAssasin can help to get reproducible builds running? If yes, we could add an encouragement to maybe find someone who can help.

[theScrabi]

I don't know it either, however there is a documentation. About it isnt it? Also i guess fdroid people would be happy to help, as they need apps using this feature.

[theScrabi]

Wupwup merged PR 2048. This means until 4096 I am not able to continue.