Superfluous `collect` in "Introduction to Julia"

[jlapeyre]

The example code following

data = collect(range(0.0, 5.0, 100))

works just as well with data = range(0.0, 5.0, 100), which does not materialize all of the elements. In the latter, the elements in data are generated as needed. This is idiomatic/recommended.

This same observation may apply in a couple of other places in the introduction.

If you are actually concerned about memory or performance in a particular instance it's worth benchmarking lazy vs. materialized array because the results might not be what you expect.