Merge pull request #48 from naumov/database_cleaner

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As described here http://www.mongodb.org/display/DOCS/Mongo+Metadata MongoDb system collections starts with system. <-- notice the dot at the end, not just with system.

This is important becouse when I have system_admins collection in my database it is not truncated. :(

So here is a fix for that case.

lib/database_cleaner/mongo/truncation.rb

@@ -14,7 +14,7 @@ module DatabaseCleaner
       private
 
       def collections
-        database.collections.select { |c| c.name !~ /^system/ }
+        database.collections.select { |c| c.name !~ /^system\./ }
       end
 
     end