Except for CreateDir, there exist repositories for each of the externals.
CreateDir is also part of, e.g., lsd_debug-tools.
ColourGradient: https://github.com/FrederikSchaff/ColourGradient
lsd_debug-tools: https://github.com/FrederikSchaff/lsd_debug-tools
Pajek: https://github.com/FrederikSchaff/PajekFromCpp

Here, fixed versions are included to simplifiy handling with git.
Time of last update: 07-April-2019
