Updated Debian/Ubuntu installation docs as installation documents for Debian and Ubuntu got obsolete.
For Ubuntu, the guide for lucid may now be deleted as it reached EOL in Apr 2015.
Update Debian/Ubuntu installation instructions.
Thanks for the great patch! :)
I think we can safely delete the "before 12.04 LTS" part in the Ubuntu section.
Remove installation guide for Ubuntu lucid.
@berkerpeksag Thanks for the review. An additional commit to remove them was pushed.