Links in README and other files

[beggsdl]

I noticed the following files have references to sites that either do not exist, or that we may not want to link to. Should they just be pointed to the Discussion and Wiki in GitHub?

Files with links (maybe there are more):

• doc/README_windows.txt
• doc/README.md
• src/qt/digibyteunits.h
• src/qt/digibyteunits.cpp

Links that exist:

• dgbwiki.com (does not exist)
• Gitter
• Telegram
• Libera
• digibytetalk.org (does not exist)