Mvdb/harvest command use argparse (#527)

* use parser.add_argument() instead of make_option()

* default values for options are already defined in the parser

* verbosity=4 is now not supported anymore (cannot remove arg with argparse)

* do not define requires_system_checks for versions lower than 1.9

* verbosity default is 3

* requires_model_validation is useful for 1.6 and below

lettuce/__init__.py

@@ -22,7 +22,6 @@ release = 'kryptonite'
 import os
 import sys
 import traceback
-import warnings
 try:
     from imp import reload
 except ImportError:
@@ -125,17 +124,11 @@ class Runner(object):
             from lettuce.plugins import dots as output
         elif verbosity is 2:
             from lettuce.plugins import scenario_names as output
-        else:
-            if verbosity is 4:
+        elif verbosity is 3:
+            if no_color:
+                from lettuce.plugins import shell_output as output
+            else:
                 from lettuce.plugins import colored_shell_output as output
-                msg = ('Deprecated in lettuce 2.2.21. Use verbosity 3 without '
-                       '--no-color flag instead of verbosity 4')
-                warnings.warn(msg, DeprecationWarning)
-            elif verbosity is 3:
-                if no_color:
-                    from lettuce.plugins import shell_output as output
-                else:
-                    from lettuce.plugins import colored_shell_output as output
 
         self.random = random