Avoiding stem imports in setup.py

Our setup.py may be ran under python 2.x or 3.x. Because of this the file and
anything it imports needs to run under both python serieses *without* a 2to3
conversion.

We were importing basic module information from __init__ which in turn brought
in the enum and str_tools utils...

atagar@morrigan:~/Desktop/stem$ python3 setup.py install
Traceback (most recent call last):
  File "setup.py", line 5, in <module>
    from stem import __version__, \
  File "/home/atagar/Desktop/stem/stem/__init__.py", line 504, in <module>
    "ERR",
  File "/home/atagar/Desktop/stem/stem/util/enum.py", line 64, in UppercaseEnum
    return Enum(*[(v, v) for v in args])
  File "/home/atagar/Desktop/stem/stem/util/enum.py", line 77, in __init__
    if isinstance(entry, (bytes, unicode)):
NameError: global name 'unicode' is not defined

Bug caught by Dererk.
Stem release 1.0.1
Adding PyPI to download page

Stem is now available on the python package index...

https://pypi.python.org/pypi/stem/

Thanks to refnode for providing us with the namespace!
Revising download page entry for the source repository

Placing the source repository at the bottom of the download page and renaming
it.
Updating ArchLinux download url

Sjon has uploaded a new AUR package for our 1.0.1 release. Pointing our
download page at that instead.
Citing ITP request in debian download page entry

Pointing the request Dererk filed for adding our release to debian.
Adding FreeBSD to our download page

Adding the stem port Carlo made for our release.
Instructions links for ArchLinux and FreeBSD

Adding the instruction links for installing via AUR and ports.
Using the official git logo

I'm a bit torn between our custom git logo and the official one. Opting for the
later in large part because it's now next to FreeBSD which has a red logo, so
this looks a little better.
Resizing FreeBSD logo

Shrinking the logo a little bit to match the other entries.
Adding Red Hat to the download page

Linking to the ticket Juan filed to add our stem release to redhat/fedora.
Emphasising installation commands

Using a preformatted block for installation commands since this is what
visitors are likely most interested in.
Revising the download page

Expanding our download page to include packaging done for our 1.0.1 release.
Many thanks to everyone involved!
Adding resource for event tutorial logo

Including the full sized image used for the 'Tortoise and the Hare' tutorial.
Python 2.6 doesn't support assertIsNotNone()

The controller integ tests included a couple assertIsNotNone() calls, which
wasn't added until python 2.7. Caught and fixed by Desoxy - thanks!

https://trac.torproject.org/8629
Still passing when tor's stime is zero

The stime proc field is an integer, rounded down to the number of seconds that
a process has been running. On my piddly little netbook tor takes long enough
to start that this is always non-zero, but on our jenkins systems it's so quick
that the test fails. Thanks to weasel for all of the help!
Improving error message when get_system_tor_version() can't find tor

When tor is unavailable the error output from get_system_tor_version() is
pretty sucky...

Traceback (most recent call last):
  File "./run_tests.py", line 525, in <module>
    our_version = stem.version.get_system_tor_version(CONFIG["argument.tor"])
  File "/home/atagar/stem/stem/version.py", line 84, in get_system_tor_version
    raise IOError(exc)
IOError: [Errno 2] No such file or directory

Making it more developer friendly.
Skipping test_get_pid_by_port when connection resolvers are unavailable

Our jenkins setup revealed that when netstat, sockstat, and lsof are all
unavailable test_get_pid_by_port fails. Skipping instead since those connection
resolvers are dependencies for the test.
Support for the ADDRMAP event's CACHED flag

Adding support for the new CACHED flag added by Desoxy...

https://trac.torproject.org/8596
https://gitweb.torproject.org/torspec.git/commitdiff/25b0d43a9ebe89541625e9f1a090e4a701748c76
Noting alternate onion images

Citing some other more artistic (but less iconic) images that I came across
while looking for a logo for stem. Might come in handy in the future and are
under Creative Commons (thanks Andrea!).