0.8.0

• Refactoring, breaking changes!
• Use time based fetching of builds and releases (eg. last 48h)
• Add stats metrics (eg. azure_devops_stats_project_release_duration)
• Add resourceusage (builds, license)
• Add export of WorkItem query results as metrics (thanks to @keremispirli )
• Add user agent to all api calls
• Use Azure DevOps API version 5.1 (some fixed versions still exists in code)
• Switch to golang 1.13
• Fixed several bugs