renamed file name to follow conventions

This is a continuation to https://github.com/yegor256/rexsl/pull/754

I have now merged master to my branch keep it up to date hence the need to submit this new pull request.

Try to understand, i am bit new to Git and it is deceptively simple, so am still learning it :)

I will follow the rules at https://github.com/tpc2/qulice/wiki/mistakes#wiki-class-names
and at http://www.tpc2.com/dev/pull

I hope now everything is OK.