Add profiling code to leapp

Also import StringIO from six.

leapp/cli/__init__.py

@@ -1,5 +1,9 @@
 import os
 import socket
+# profiling
+import cProfile
+import pstats
+import six
 
 from leapp.utils.clicmd import command, command_opt
 from leapp.cli import upgrade
@@ -12,7 +16,18 @@ def cli(args): # noqa; pylint: disable=unused-argument
 
 
 def main():
+    profile_enabled = os.environ.get('LEAPP_CPROFILE', '0') == '1'
+    if profile_enabled:
+        pr = cProfile.Profile()
+        pr.enable()
     os.environ['LEAPP_HOSTNAME'] = socket.getfqdn()
     for cmd in [upgrade.list_runs, upgrade.preupgrade, upgrade.upgrade, upgrade.answer]:
         cli.command.add_sub(cmd.command)
     cli.command.execute('leapp version {}'.format(VERSION))
+    if profile_enabled:
+        pr.disable()
+        s = six.StringIO()
+        sortby = 'cumulative'
+        ps = pstats.Stats(pr, stream=s).sort_stats(sortby)
+        ps.print_stats()
+        print(s.getvalue())

leapp/snactor/__init__.py

@@ -1,17 +1,10 @@
 import os
 import pkgutil
 import socket
-
 # for profilling
 import cProfile
 import pstats
-try:
-    from StringIO import StringIO
-except ImportError:
-    # TODO: low possibility of the problem with encoding with Python3;
-    # # but it should not be so problematic in this case, so keeping now just
-    # # like that to keep it simple
-    from io import StringIO
+import six
 
 from leapp.utils.i18n import _  # noqa; pylint: disable=redefined-builtin
 from leapp.snactor import commands
@@ -93,7 +86,7 @@ def main():
     cli.command.execute(version=_('snactor version {}').format(VERSION))
     if profile_enabled:
         pr.disable()
-        s = StringIO()
+        s = six.StringIO()
         sortby = 'cumulative'
         ps = pstats.Stats(pr, stream=s).sort_stats(sortby)
         ps.print_stats()