Review of examples/fetch

[iesahin]

This is the review of https://www.katacoda.com/dvc/courses/examples/fetch

• "As a prerequisite, you have to study first the Get Started tutorial, otherwise it may be a bit difficult to understand the structure of the project" can be rephrased.

• dvc remove *.dvc data/*.dvc returns an error

• prepare.dvc refers to an early version of example-get-started

cat \ data/data.xml.dvc \ prepare.dvc | grep path:

• dvc fetch with specific stages should be updated.

This is related with epic iterative/dvc.org#1400