Remove fuel-devops.devops.manager.Manager class.
Split models.py into separate parts.
Change Environment model's interface.
Change database name from 'postgres' to 'fuel-devops'.
Reform imports.
Move methods from fuel-main.fuelweb_test.models.EnvironmentModel to
fuel-devops.devops.models.Environment.
Update package version from 2.6.9. to 2.9.0
Change-Id: I8de449193df44b70ddeb1b0709698ebfe0120c77
Implements: blueprint system-tests-and-devops-refactoring
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