fix main.py

schmohl1@troulwn1000:~/workspace/Simulator (master)
$ git tessera ll
unknown command: ll
Traceback (most recent call last):
  File "/usr/local/bin/git-tessera", line 9, in <module>
    load_entry_point('git-tessera==0.00.03', 'console_scripts', 'git-tessera')()
  File "/usr/local/lib/python2.7/dist-packages/git_tessera-0.00.03-py2.7.egg/tessera/main.py", line 29, in main
    colorful.out.underline("%s - %s" % (cmd[4:], cmd.func_doc))
AttributeError: 'str' object has no attribute 'func_doc'