Quickly get files to refactor

They are usually the most changed ones:

git log --pretty=format: --name-only | grep .rb | sort | uniq -c | sort -rg | head -10

Or has been fixed the most:

git log --grep fix --pretty=format: --name-only | sort | uniq -c | sort -rg | head -10

Or contain too much logic:

wc -l app/models/* | sort | tail