Add 'scala-jar' to the list of jar artifacts.
Add 'scala-jar' to the list of jar artifacts.

The CustomPomParser has a hard-coded list of 'blessed' Maven POM packaging types
that are actually packaged as jar files, but Ivy incorrectly maps the file extension.
This patch allows artifacts published with the 'scala-jar' packaging to be properly
resolved and used in an SBT project.

jkinkead/sbt,mdedetrich/sbt,mdedetrich/sbt,jasonchaffee/sbt,mdedetrich/sbt,mdedetrich/sbt,adriaanm/sbt,pdalpra/sbt,Duhemm/sbt,jkinkead/sbt,mdedetrich/sbt,twitter-forks/sbt,dyx/sbt,mdedetrich/sbt,xuwei-k/xsbt,sbt/sbt,twitter-forks/sbt,dyx/sbt,sbt/sbt,xuwei-k/xsbt,Sciss/sbt,som-snytt/xsbt,sbt/sbt,xuwei-k/xsbt,sbt/sbt,pocketberserker/sbt,dyx/sbt,xuwei-k/xsbt,Duhemm/compiler-bridge,Duhemm/sbt,sbt/sbt,twitter-forks/sbt,corespring/sbt,dyx/sbt,sbt/sbt,xuwei-k/xsbt,dyx/sbt,jkinkead/sbt,jkinkead/sbt,twitter-forks/sbt,dansanduleac/sbt,twitter-forks/sbt,sbt/sbt,jkinkead/sbt,mdedetrich/sbt