Code refactoring - Watcher Applier package

This patchset is there to change the code structure.
The objective is to flatten the project file tree by merging
'api/' and 'framework/' into a single package. This also contains
some tidy ups in package naming (like using only singular nouns).

This should only affect file/folder names and their subsequent
import paths wherever they were used.

Change-Id: Id7b37667c613086d8ef3cd1f367c4219bf026fc7

watcher/cmd/applier.py

@@ -24,7 +24,7 @@ import sys
 from oslo_config import cfg
 from oslo_log import log as logging
 
-from watcher.applier.framework.manager_applier import ApplierManager
+from watcher.applier.manager import ApplierManager
 from watcher.common import service
 from watcher import i18n