SONAR_TOKEN can be generated by going to SonarQube.com and navigating to My Account and going to Security after you logged in. Generate a new token (the name does not matter) and copy the token somewhere for safe keeping.
SONAR_GITHUB_TOKEN can be generated by going to your GitHub account settings under Personal Access Tokens. Generate a new access token with
repo privileges. If you are only dealing with open source stuff then using
public_repo is enough.
Enabling Travis for the repo
Go to your profile in Travis and just flick the button to On for your repository.