I installed Parsoid fine on ubuntu two weeks ago, but just trying the same commands I get:
Unable to locate package parsoid
Here's my recent commands
14 sudo apt-key advanced --keyserver keys.gnupg.net --recv-keys 90E9F83F22250DD7
15 sudo apt-get update
16 sudo apt-get install apt-transport-https
17 sudo apt-get update && sudo apt-get install parsoid
18 nodejs -v
19 which nodejs
20 cat /etc/*-release
21 wget -qO- https://deb.nodesource.com/setup_4.x | sudo bash -
22 sudo apt-get install nodejs
23 which nodejs
24 nodejs -v
25 sudo apt-get update && sudo apt-get install parsoid
26 sudo apt-add-repository "deb https://releases.wikimedia.org/debian jessie-mediawiki main"
27 sudo apt-get install parsoid