Rewrite lines for download / parse messages

This commit changes the previous behavior in the
application to write out a sequence of lines for
every single new download / process progress
margin. The new behavior writes the progress,
then the next behavior overwrites the previous
message, ultimately only leaving a "100%" message.

Here is an example. Previously:
```
Downloading: GeoLiteCity.dat.gz Bytes: 11896864
0.1% [                                   ]
1.0% [                                   ]
2.0% [                                   ]
```

Now:
```
Downloading: GeoLiteCity.dat.gz Bytes: 11896864
3.4% [=                                  ]
```

This is also changed for the "Processing IPs"
message. I also added the `web/data.json` file
to the `.gitignore`.