Add options --clean and --no-clean in runtest.py

--no-clean option speeds up repeating test execution by skipping the cleanup
process before and after testing.

Typical use case command could look like

./runtests.py -vv --no-clean --name integration.modules.ssh

tests/integration/__init__.py

@@ -39,6 +39,10 @@ class TestDaemon(object):
     '''
     Set up the master and minion daemons, and run related cases
     '''
+
+    def __init__(self, clean):
+        self.clean = clean
+
     def __enter__(self):
         '''
         Start a master and minion
@@ -142,6 +146,8 @@ class TestDaemon(object):
         '''
         Clean out the tmp files
         '''
+        if not self.clean:
+            return
         if os.path.isdir(self.sub_minion_opts['root_dir']):
             shutil.rmtree(self.sub_minion_opts['root_dir'])
         if os.path.isdir(self.master_opts['root_dir']):

tests/runtests.py

@@ -60,7 +60,7 @@ def run_integration_tests(opts):
     if not any([opts.client, opts.module, opts.runner,
                 opts.shell, opts.state, opts.name]):
         return status
-    with TestDaemon():
+    with TestDaemon(clean=opts.clean):
         if opts.name:
             results = run_suite(opts, '', opts.name)
             status.append(results)
@@ -152,6 +152,17 @@ def parse_opts():
             dest='name',
             default='',
             help='Specific test name to run')
+    parser.add_option('--clean',
+            dest='clean',
+            default=True,
+            action='store_true',
+            help=('Clean up test environment before and after '
+                  'integration testing (default behaviour)'))
+    parser.add_option('--no-clean',
+            dest='clean',
+            action='store_false',
+            help=('Don\'t clean up test environment before and after '
+                  'integration testing (speed up test process)'))
 
     options, _ = parser.parse_args()
     if not any((options.module, options.client,