Upgraded Jenkins and base OS versions, added support to Flex shapes

[lucassrg]

• Upgraded Jenkins to latest available version
• Upgraded template to support OCI Compute Flex shapes
• Fixed data source to fetch images compatible with shapes - required data source for each instance/image
• Upgraded base OS from OL 7.8 to OL.79 which required changes to the installation script
  • Removed xmlstarletpackage dependencies from script
  • Added some logic on waitForJenkins function when it fails to connect to the server
• Formatted code
• Refactored code
  • added locals to its own file
  • added CLI specific Provider variables into provider.tf
  • added versions.tf containing provider minimum version support

[lfeldman]

I have merged the code. Now working on the new release.