Install npm on Ubuntu when not using PPA

On Ubuntu, if we're not using the PPA, the npm package does need
to be explicitly installed. Modify the boolean logic around the
trap to only skip installing it on Ubuntu if we are, in fact,
also managing the PPA.
how about we handle this without an if surrounding this `package` but with a package name, and anchor of `undef` for all cases of operating systems that have their npm package in the bloody node package. (seriously what GOOD is splitting those two? They are useless without each other)