Build for scala 2.11

Hi,

  I've build widgets module for Scala 2.11. Could you please integrate? In addition I removed unnecessary dependencies and upgrade sbt, log4j and logback to the latest versions.
while we don't have any tests right now, I'd like to have these dependencies in place, so that it would  be easier to add tests in the future, to have the right specs for each scala version, you can see here:
https://github.com/liftmodules/jta/pull/5/files#diff-fdc3abdfd754eeb24090dbd90aeec2ceR48