Make READMe more generic and remove specific mentions to release versions

• README file made generic
• References to documents of specific version will point directly to the release version if we have installed a release (tag), if not they will always point to the main branch. Alternatively we can make them point to the current branch but I think to main is good enough.
• With these changes we won't have to manually update the versions everytime, we just need to update the Google docs.