Install Linux headers in Kali

In Kali Linux 2016.2, Linux headers were not installed when build-essential package was installed. Linux-headers is need when installing VirtualBox guest additions. To install the headers, do:

# apt install linux-headers-$(uname -r)

This should apply to the following distribution as well:
- Debian
- Ubuntu and derivatives

Reference(s):
http://askubuntu.com/questions/75709/how-do-i-install-kernel-header-files