README/Chapter 1: make test won't work before gtest is built

[mbeyeler]

Imported from CARLsim3, applies to README/User Guide Chapter 1 of CARLsim4, too:

From @SigmaX :

Since we include gtest as a submodule, building tests is easy and convenient.

But the README suggest that building the tests is as simple as running make test after checkout. This won't work until gtest has been built—that that takes a few steps.

We should update the README to direct users to the gtest README, and to build the gtest library in the designated path.

[mbeyeler]

An alternative would be to have make test automatically compile gtest if needed (i.e., run the cmake recipe as part of make test).

[Amri95]

An alternative would be to have make test automatically compile gtest if needed (i.e., run the cmake recipe as part of make test).

Hello there,
I want to install CARLsim4 to my virtual system "ubuntu16.04" without GPU. Can you please provide me step by step guidelines. Hard to understand the installation procedure.
Best Regards