updated the intro explanation to clustering.ipynb

[yoid2000]

I also ran both clustering.ipynb and tutorial.ipynb, which created a lot of changes

[cristianberneanu]

There is a lot of noise here because of the changes that appear when re-running a notebook. You can select individual changes to add to a commit by executing:

git add -p docs/clustering.ipynb

After the commit is made, you can drop the unwanted changes from the file with:

git checkout docs/clustering.ipynb

[yoid2000]

Should I try that now, or is it too late?

[edongashi]

Changes look fine. I'd get rid of the installation messages.

Should I try that now, or is it too late?

If you want to, we can force push the branch with only relevant changes, or we can create a new cleaned up PR.

[cristianberneanu]

It isn't too late, since it wasn't merged. You can restart the previous commit by executing:

git reset HEAD^

Also, you can manually clear notebook cells with useless outptut (like the ones for installing packages).