Refer readers to our tutorial before referring them to existing bst projects
Previously, in README.md, we would refer readers to other existing BuildStream projects (including two which do not currently 'build') to get started, and not to our own tutorial.
This patch does the following:
- Directs users towards our tutorials before directing them towards other projects
- Removes the projects that do not currently 'build'
- Rewording of "How does BuildStream work?" points, fix a typo, capitalised some words
- Adds a note to main_install.rst, requesting that macOS and Windows users refer to BuildStream inside Docker
Edited by James Ennis