Ascii server

[dmasad]

Implementing a simple server which displays TextVisualization ascii visualizations in-browser, with 'Step' and 'Reset' buttons. Demonstrates how to template a page based on a visualization, and then populate it with step-by-step data generated from a model object.
Resolves Issue #26 (now with issue #33 fixed as well)

[kfuruya]

Give an actual example please. "data": some text unparseable by actual json is unhelpful for building APIs

[kfuruya]

So I was testing and ran into this crash:

Socket opened!
WARNING:tornado.access:404 GET /favicon.ico (127.0.0.1) 0.55ms
{"type":"get_step","step":0}
{"type":"get_step","step":1}
{"type":"get_step","step":2}
...
{"type":"get_step","step":9}
{"type":"get_step","step":10}
{"type":"reset"}
('Model steps:', 26)
{"type":"get_step","step":1}
{"type":"get_step","step":2}
...
{"type":"get_step","step":26}
{"type":"get_step","step":27}
ERROR:tornado.application:Uncaught exception in /ws
Traceback (most recent call last):
  File "/Users/kfuruya/.virtualenvs/mesa/lib/python2.7/site-packages/tornado/websocket.py", line 369, in _run_callback
    callback(*args, **kwargs)
  File "/Users/kfuruya/mesa/mesa/visualization/TextServer.py", line 113, in on_message
    return_message["data"] = self.controller.viz_states[step]
IndexError: list index out of range

I'm going to look into this, but it seems like it crashed well within the realm of expected use

[dmasad]

Yep, should be an easy error to fix. Opened Issue #33 to deal with it.