improve turbo mode support (#117)

- delay the loading of external modules when possible
- delay the loading of OKDRawModule and OpenShiftProcess classes
- k8s reuse the design of the kubernetes.core modules

We've got a chicken/egg problem that prevent us from properly
reporting if kubernetes.core is missing. We need args_common to create
the module object. And we need the module object to report the missing
dependency. The dependency is declared in the galaxy.yml file anyway,
the problem should not happen.

tests/sanity/ignore-2.10.txt

@@ -1,4 +1,4 @@
 plugins/modules/k8s.py validate-modules:parameter-type-not-in-doc
 plugins/modules/k8s.py validate-modules:return-syntax-error
-plugins/modules/k8s.py pylint:bad-option-value
+plugins/module_utils/k8s.py pylint:bad-option-value
 plugins/modules/openshift_process.py validate-modules:parameter-type-not-in-doc

tests/sanity/ignore-2.11.txt

@@ -1,4 +1,4 @@
 plugins/modules/k8s.py validate-modules:parameter-type-not-in-doc
 plugins/modules/k8s.py validate-modules:return-syntax-error
-plugins/modules/k8s.py pylint:bad-option-value
+plugins/module_utils/k8s.py pylint:bad-option-value
 plugins/modules/openshift_process.py validate-modules:parameter-type-not-in-doc

tests/sanity/ignore-2.9.txt

@@ -1,3 +1,3 @@
 plugins/modules/k8s.py validate-modules:parameter-type-not-in-doc
-plugins/modules/k8s.py pylint:bad-option-value
+plugins/module_utils/k8s.py pylint:bad-option-value
 plugins/modules/openshift_process.py validate-modules:parameter-type-not-in-doc