apply update BIC of Sberbank
change gem version to non pre-release

A version like `0.1.4.20140907a` is considered a pre-release version.
So we yank and replace it with `0.1.4.20140907.1`.
Merge branch 'master' of github.com:olivere/blz
finders return an empty array on blank argument

When given nil or a blank string, the finders will return
an empty array now.