Add "excommunicate" debug option

Some debuggers are easier to work with when we do everything in a single
process.  This debug option caters to that at the expense of being
different from what Ansible will actually do to invoke a module.

When we document this we should be clear that this shouldn't be used for
general purpose debugging and that some modules may show strange
"errors" when used with this.  Those won't be considered real bugs as
it's not how ansible really invokes the modules.

lib/ansible/executor/module_common.py

@@ -109,6 +109,10 @@ def debug(command, zipped_mod):
     # Okay to use __file__ here because we're running from a kept file
     basedir = os.path.dirname(__file__)
     if command == 'explode':
+        # transform the ZIPDATA into an exploded directory of code and then
+        # print the path to the code.  This is an easy way for people to look
+        # at the code on the remote machine for debugging it in that
+        # environment
         import zipfile
         z = zipfile.ZipFile(zipped_mod)
         for filename in z.namelist():
@@ -124,8 +128,12 @@ def debug(command, zipped_mod):
                 f = open(dest_filename, 'w')
                 f.write(z.read(filename))
                 f.close()
-        print('Module expanded into: %%s' %% os.path.join(basedir, 'ansible'))
+        print('Module expanded into:')
+        print('%%s' %% os.path.join(basedir, 'ansible'))
     elif command == 'execute':
+        # Execute the exploded code instead of executing the module from the
+        # embedded ZIPDATA.  This allows people to easily run their modified
+        # code on the remote machine to see how changes will affect it.
         pythonpath = os.environ.get('PYTHONPATH')
         if pythonpath:
             os.environ['PYTHONPATH'] = ':'.join((basedir, pythonpath))
@@ -140,6 +148,18 @@ def debug(command, zipped_mod):
         sys.stderr.write(stderr)
         sys.stdout.write(stdout)
         sys.exit(p.returncode)
+    elif command == 'excommunicate':
+        # This attempts to run the module in-process (by importing a main
+        # function and then calling it).  It is not the way ansible generally
+        # invokes the module so it won't work in every case.  It is here to
+        # aid certain debuggers which work better when the code doesn't change
+        # from one process to another but there may be problems that occur
+        # when using this that are only artifacts of how we're invoking here,
+        # not actual bugs (as they don't affect the real way that we invoke
+        # ansible modules)
+        sys.path.insert(0, basedir)
+        from ansible.module_exec.%(ansible_module)s.__main__ import main
+        main()
 
 os.environ['ANSIBLE_MODULE_ARGS'] = %(args)s
 os.environ['ANSIBLE_MODULE_CONSTANTS'] = %(constants)s