Consistency in the dataframe column names

[tnzmnjm]

We have a mix of column names with underscores for separators between words (e.g. base_repo_url) and other names that are simply joined into a long word (e.g. testfilecountlocal). We need to consistent.

[julianharty]

Let's also see how we can revise the names so they communicate their purpose clearly e.g. base_repo_url_flag is unnecessarily vague, a more purposeful name might be: base_repo_url_extracted_successfully; and I suspect we might devise even clearer names.

As a historical note, Hungarian Notation was once used extensively and it uses a prefix of f to indicate the data type is a flag. Hungarian Notation is not recommended by many people these days; and especially not recommended in python.