Tutorials are not standalone

[odow]

The tutorials use this DATA_DIR variable which is hidden https://github.com/NREL-SIIP/PowerSystems.jl/blob/eab51ddf29d6d37f62b0c2f160bc7bd632bacee2/docs/src/modeler_guide/modeling_with_JuMP.jl#L20-L21 That makes it a bit confusing

I assume what's missing in the general

using PowerSystems
DATA_DIR = download(PowerSystems.UtilsData.TestData, folder = pwd())

[jd-lara]

Thanks for the fix, I will review the rest of the docs to fix this if it happens elsewhere.