Issue: Instaler requires root #33

Currently when you install nan cli with command:

curl -fsSL https://nan.builders/install | bash

It requires root password because it is instaling the cli in /usr/local/bin it should be installed in ${HOME}/.local/bin instead and make sure that path is on PATH var, if it isn't then just add to ~/.profile:

export PATH="${PATH:+${PATH}:}${HOME}/.local/bin"

To check if route is on path already you can use conditional in install script like:

    if [[ -d "${HOME}/.local/bin" && ":$PATH:" != *":${HOME}/.local/bin:"* ]]; then
        export PATH="${PATH:+${PATH}:}${HOME}/.local/bin"
    fi