Describe the issue linked to the documentation

Found a small typo error under the readme file.
The text mentions "If you already have a working installation of numpy and scipy," but it should be "If you already have a working installation of NumPy and SciPy," with "NumPy" and "SciPy" capitalized correctly.

Should look like:
"If you already have a working installation of NumPy and SciPy, the easiest way to install scikit-learn is using pip."

Suggest a potential alternative/fix

No response