DDD Refactor: Move infrastructure.py to infrastructure layer

Make imports available as module.

src/main/python/ddadevops/infrastructure/__init__.py

@@ -0,0 +1 @@
+from .infrastructure import FileApi, ImageApi, ResourceApi, ExecutionApi, ProjectRepository

src/main/python/ddadevops/infrastructure/infrastructure.py

@@ -4,8 +4,8 @@ from os import chmod
 from subprocess import run
 from pkg_resources import resource_string
 import yaml
-from .domain import Devops, Image, C4k, ReleaseConfig
+from ..domain import Devops, Image, C4k, ReleaseConfig
-from .python_util import execute
+from ..python_util import execute
 
 
 class ProjectRepository: