add support for quandl historical financial data
| Q | A |
| --- | --- |
| Bug fix? | no |
| New feature? | yes |
| BC breaks? | no |
| Deprecations? | no |
| Tests pass? | yes |
| Fixed tickets | - |
| License | BSD |
| Doc PR | - |

Getting a few Travis build errors trying to install dependencies that don't seem related to this PR?

```
Error: HTTPError: 403 Client Error: Forbidden: http://conda.binstar.org/pandas/linux-64/beautiful-soup-4.2.1-py27_0.tar.bz2
```

```
Error: HTTPError: 403 Client Error: Forbidden: http://conda.binstar.org/pandas/linux-64/bottleneck-0.8.0-np18py33_0.tar.bz2
```
 Sumit this PR to https://github.com/pydata/pandas-datareader/issues

once that is merged we could consider porting back to main pandas 

in 0.17.0 all of the datareader is going to be ripped out and pandas-dataeader  will be the source for things like this
