The "Installing Python Development Headers" and "Installing patch"
sections have been combined into a single "Installing Required
Dependencies" section, to reduce the number of steps. This section also
lists the dependencies that we now require for cryptography, and lists
packages needed to perform general compilation on the system. This
should help keep installation smooth for new users.

Built the docs and checked to make sure they were referring to the

correct packages and that links weren't affected negatively.