Fix for #142. Simply ignores lines that begin with ' ='

[nefaspartim]

This is kind of a hacky fix for #142. It works in all test cases using git 1.8.3.1 and 1.9.2, so I assume it won't break stuff. Please examine and subsequently make fun of me.

[Byron]

Well, let's try that - I am suffering from that issues as well by the way and grow more annoyed by it every day.
Thanks for your contribution !

[rkyser]

This breaks fetching individual remotes. I'm using git version 1.9.2.msysgit.0.

>>> from git import Repo
>>> r = Repo('.')
>>> r.remotes['origin'].fetch()
Traceback (most recent call last):
  File "<stdin>", line 1, in <module>
  File "C:\Python27\lib\site-packages\gitpython-0.3.2.rc1-py2.7.egg\git\remote.py", line 594, in fetch
    return self._get_fetch_info_from_stderr(proc, progress or RemoteProgress())
  File "C:\Python27\lib\site-packages\gitpython-0.3.2.rc1-py2.7.egg\git\remote.py", line 540, in _get_fetch_info_from_stderr
    assert len(fetch_info_lines) == len(fetch_head_info), "len(%s) != len(%s)" % (fetch_head_info, fetch_info_lines)
AssertionError: len(["26a25a032bc442de391425e89be07124ea2ba845\t\tbranch 'master' of fake.url.com:gint/testrepo1\n", "59d3007c47269d7bb2b3c464a6ed290ec9a95a6f\tnot-for-merge\tbranch 'RemoteOnlyBranch_DontCheckout' of fake.url.com:gint/testrepo1\n", "43ce9f5dd15f817eb806331648ed70e82e3b8b06\tnot-for-merge\tbranch 'branch1' of fake.url.com:gint/testrepo1\n"]) != len([])

If I remove or line.startswith(' ='):

>>> from git import Repo
>>> r = Repo('.')
>>> r.remotes['origin'].fetch()
[<git.remote.FetchInfo object at 0x02550DA0>, <git.remote.FetchInfo object at 0x02550F30>, <git.remote.FetchInfo object at 0x02550E90>]