KG: track if the readme has been modified

[ciyer]

Description

It would be useful know know if the README is the autogenerated default or if it has been modified. The UI intends to use this information to 1. Either show or not show the Readme on the project main page 2. Build a "project quality assistant" that would suggest improvements to the project to users.

The KG should include a field on project has_readme. If the readme file is the autogenerated one, this will be false.

Implementation

The easiest way to implement this is to see if there are any commits on the README.md file. This should be acceptable. This information should be stored in the KG.