Refresh SQ Docs

[colin-sonarsource]

https://discuss.sonarsource.com/t/dockerhub-description/8190/2

• What is SonarQube?
  • We have Boilerplate guidelines when describing SonarQube we could use, beyond the current 12 word description. It has been added.
• How to use this image
  • Using “Data Center” Edition rather than DataCenter Edition
• Docker Host Requirements
  • Due for an update based on current requirements
• Get Started in Two Minutes Guide
  • We’ve moved towards wording like Try Out SonarQube
• First Installation
  • The "first" installation is usually when they've tried out SonarQube above? This section is where they get serious about installation (and then configuration), so it's been renamed.
• Configuration > Database
  • “Data Center” Edition rather than Datacenter Edition
• Configuration > Use volumes
  • Now that v7.9 LTS is EOL, can we remove reference to the /opt/sonarqube/conf persistent volume
  • “Data Center” Edition rather than DataCenter Edition
• Advanced configuration > Customized Image
  • Time to bump this example to sonarqube:8.9-community which means removing the /opt/sonarqube/conf/ example and replacing it with another (adding a custom plugin)
• Advanced configuration > Avoid hard termination of SonarQube
  • SonarQube v7.8 was a while ago (and EOL). We now avoid mentioning it and just stick to discussing the hard termination of SonarQube.

[tobias-trabelsi-sonarsource]

LGTM.
would you mind updating the host requirements here as well to match the values we have in our docs ? Else i will handle this in a separate PR

[colin-sonarsource]

@tobias-trabelsi-sonarsource done :)

[MikeBirnstiehl]

LGTM