[after review+update] streamline GS workflow to be minimalistic

[mishaone]

This means probably move out the debugging stuff and anything else that is more advanced to streamline the GS doc workflow to be quick, efficient and present a quick path to openshift.

[Preeticp]

We need to remove Using advanced Che features from GS and probably add it to the UG, currently it is already in the smaller user story.

[Preeticp]

Considering openshiftio/openshift.io#4656, the 9th chapter in GS: Optimizing your memory usage could probably be moved to UG (Explore)