QRPedia doesn't recognize converttitles option

```
What steps will reproduce the problem?
1. Go to http://qrpedia.org
2. Enter http://sr.wikipedia.org/wiki/Beograd URL

QRPedia says "Sorry - that doesn't seem to be a valid Wikipedia URL" while it
is.

This is because sr.wikipedia uses the converttitles MediaWiki option that
QRPedia doesn't recognize. This is solved in the attached patches (along with a
few other tiny issues). Use of converttitles will have no effect on Wikipedias
that don't use this option.
```

Original issue reported on code.google.com by `nikola.s...@gmail.com` on 9 Sep 2013 at 2:03

Attachments:
- [index.diff](https://storage.googleapis.com/google-code-attachments/qrwp/issue-20/comment-0/index.diff)
- [qrpedia_index.diff](https://storage.googleapis.com/google-code-attachments/qrwp/issue-20/comment-0/qrpedia_index.diff)

Start by reproducing the failure with http://sr.wikipedia.org/wiki/Beograd, then inspect the attached index.diff and qrpedia_index.diff for the proposed converttitles handling. Done means QRPedia accepts this valid Serbian Wikipedia URL while preserving validation for Wikipedias that do not use the option.

Written by the indexing model from the issue text.