Fix pep8 deps for pyflakes version conflict.

Fixes bug 1199400.

* tox.ini: In the pep8 environment, flake8 and hacking were both
listed as deps. This was fine while both worked with the latest
pyflakes, but then pyflakes 0.7.3 came along and was getting
installed before the more explicit pyflakes 0.7.2 requirement was
parsed for hacking. Since flake8 is in the requirements list for
hacking anyway, this just removes it from the pep8 environment deps
list.

Change-Id: I647235a4f6d109e00f13a156c57ff3a0e9a13a81
Fix str(None) bug in port detection for hook setup

1) when git-review -s is launched it tries to detect
   information for scp-ing the commit-msg hook from remote.
2) when remote url does not contains port (':number')
   we'll get None from urlparse.
3) just before passing it further it was always converted
   to string (and so we could get 'None')
4) Later if port is not None, we add '-P {port}' to the scp command.

Which caused scp failure with message 'Bad port None'.

So we convert port to str only if it's not None.

Change-Id: I64c7a197844027cb24c13817d6c3186009568e8a
Pin hacking <0.6

* tox.ini: Newer hacking fails to recognize the Apache header in the
git-review script, so pin at <0.6 for now to match an upcoming
refactoring change. This will allow us to get some quick cosmetic
fixes in first.

Change-Id: I8e92b1d23d0b8d87e3bafe43d97c987abdf1d9f8
Wrap long lines

* git-review: Long lines of output are wrapped for readability.

Change-Id: I63c01585a28137b2a09557c0a41589348c23ebbb