DR-936 - Additions to onboarding docs (#450)
DR-936 - Additions to onboarding docs (#450)

* First pass

* Adding some common issues

* cleanup

* cleanup

* Combine postgres steps

* Address rest of comments

* small cleanup

* Format and update getting started document

Co-authored-by: Shelby <7c362572ebb6384b20064798792f864f6b068bd6@gmail.com>
Co-authored-by: Florian Boulnois <a4c7704594870c27f12c0888ff911a66b410e9b3@broadinstitute.org>
DataBiosphere/jade-data-repo,DataBiosphere/jade-data-repo,DataBiosphere/jade-data-repo,DataBiosphere/jade-data-repo