Flake8 fixes (#35)

* Apply Flake8 also on `setup.py`

modified:   tox.ini

* Fix W605 - invalid escape syntax

modified:   packages/setup.py
modified:   tox.ini

* Update comment about Flake8: W504

W503 and W504 are mutual exclusive - so we have to keep one of them.

modified:   tox.ini

* Fix F841 - variable assigned but never used

modified:   ssh-audit.py
modified:   tox.ini

* Fix E741 - ambiguous variable name 'l'

modified:   ssh-audit.py
modified:   tox.ini

* Fix E712 - comparison to False should be 'if cond is False'

... and not 'if conf == False'.

modified:   ssh-audit.py
modified:   tox.ini

* Fix E711 - comparison to None should be 'if cond is not None'

... and not 'if cond != None'.

modified:   ssh-audit.py
modified:   tox.ini

* Fix E305 - expected 2 blank lines

... after class or function definition, found 1.

modified:   ssh-audit.py
modified:   tox.ini

* Fix E303 - too many blank lines

modified:   ssh-audit.py
modified:   tox.ini

* Fix E303 - too many blank lines

modified:   ssh-audit.py
modified:   tox.ini

* Fix E301 - expected 1 blank line, found 0

No code change necessary, probably fixed by another commit.

modified:   tox.ini

* Fix E265 - block comment should start with '# '

There is lots of commented out code, which usually should be just
deleted.

I will keep it for now, as I am not yet very familiar with the code
base.

modified:   ssh-audit.py
modified:   tox.ini

* Fix E261 - at least two spaces before inline comment

modified:   ssh-audit.py
modified:   tox.ini

* Fix E251 - unexpected spaces around keyword / parameter equals

modified:   packages/setup.py
modified:   tox.ini

* Fix E231 - missing whitespace after ','

No code change necessary, probably fixed by previous commit.

modified:   tox.ini

* Fix E226 - missing whitespace around arithmetic operator

modified:   ssh-audit.py
modified:   tox.ini

* Fix W293 - blank line contains whitespace

modified:   ssh-audit.py
modified:   tox.ini

* Fix E221 - multiple spaces before operator

modified:   ssh-audit.py
modified:   tox.ini

* Update comment about Flake 8 E241

Lots of data is formatted as tables, so this warning is disabled for a
good reason.

modified:   tox.ini

* Fix E401 - multiple imports on one line

modified:   ssh-audit.py
modified:   tox.ini

* Do not ignore Flake8 warning F401

... as there were no errors in source code anyway.

modified:   tox.ini

* Fix F821 - undefined name

modified:   ssh-audit.py
modified:   tox.ini

* Reformat ignore section for Flake8

modified:   tox.ini

* Flake8 test suite

modified:   test/conftest.py
modified:   test/test_auditconf.py
modified:   test/test_banner.py
modified:   test/test_buffer.py
modified:   test/test_errors.py
modified:   test/test_output.py
modified:   test/test_resolve.py
modified:   test/test_socket.py
modified:   test/test_software.py
modified:   test/test_ssh1.py
modified:   test/test_ssh2.py
modified:   test/test_ssh_algorithm.py
modified:   test/test_utils.py
modified:   test/test_version_compare.py
modified:   tox.ini

test/test_output.py

@@ -10,7 +10,7 @@ class TestOutput(object):
 	def init(self, ssh_audit):
 		self.Output = ssh_audit.Output
 		self.OutputBuffer = ssh_audit.OutputBuffer
-	
+
 	def test_output_buffer_no_lines(self, output_spy):
 		output_spy.begin()
 		with self.OutputBuffer() as obuf:
@@ -21,13 +21,13 @@ class TestOutput(object):
 			pass
 		obuf.flush()
 		assert output_spy.flush() == []
-	
+
 	def test_output_buffer_no_flush(self, output_spy):
 		output_spy.begin()
 		with self.OutputBuffer():
 			print(u'abc')
 		assert output_spy.flush() == []
-	
+
 	def test_output_buffer_flush(self, output_spy):
 		output_spy.begin()
 		with self.OutputBuffer() as obuf:
@@ -36,14 +36,14 @@ class TestOutput(object):
 			print(u'def')
 		obuf.flush()
 		assert output_spy.flush() == [u'abc', u'', u'def']
-	
+
 	def test_output_defaults(self):
 		out = self.Output()
 		# default: on
 		assert out.batch is False
 		assert out.use_colors is True
 		assert out.level == 'info'
-	
+
 	def test_output_colors(self, output_spy):
 		out = self.Output()
 		# test without colors
@@ -82,7 +82,7 @@ class TestOutput(object):
 		output_spy.begin()
 		out.fail('fail color')
 		assert output_spy.flush() == [u'\x1b[0;31mfail color\x1b[0m']
-	
+
 	def test_output_sep(self, output_spy):
 		out = self.Output()
 		output_spy.begin()
@@ -90,7 +90,7 @@ class TestOutput(object):
 		out.sep()
 		out.sep()
 		assert output_spy.flush() == [u'', u'', u'']
-	
+
 	def test_output_levels(self):
 		out = self.Output()
 		assert out.get_level('info') == 0
@@ -98,7 +98,7 @@ class TestOutput(object):
 		assert out.get_level('warn') == 1
 		assert out.get_level('fail') == 2
 		assert out.get_level('unknown') > 2
-	
+
 	def test_output_level_property(self):
 		out = self.Output()
 		out.level = 'info'
@@ -111,7 +111,7 @@ class TestOutput(object):
 		assert out.level == 'fail'
 		out.level = 'invalid level'
 		assert out.level == 'unknown'
-	
+
 	def test_output_level(self, output_spy):
 		out = self.Output()
 		# visible: all
@@ -150,7 +150,7 @@ class TestOutput(object):
 		out.warn('warn color')
 		out.fail('fail color')
 		assert len(output_spy.flush()) == 1
-	
+
 	def test_output_batch(self, output_spy):
 		out = self.Output()
 		# visible: all