ZeroMQ, pkg-config, UUID, and Doxygen

On Ubuntu 14.04 LTS, these packages can be installed as follows:

$ sudo apt-get install pkg-config libzmq3-dev doxygen graphviz-dev uuid-dev

On macOS, we recommend installing with Brew:

$ brew install ossp-uuid pkg-config zeromq doxygen

The pkg-config program and UUID library are only available on Unix-like systems. 

On Windows, using the MSYS2 environment, these dependencies can be installed as follows (assuming the 64-bit version):

$ pacman -S mingw64/mingw-w64-x86_64-zeromq
$ pacman -S mingw64/mingw-w64-x86_64-pkg-config
$ pacman -S mingw64/mingw-w64-x86_64-doxygen
$ pacman -S mingw64/mingw-w64-x86_64-graphviz