Update Polish translation

changed the build.xml of transferguard to copy compiled jar to the target directory.

It seems that the transferguard.jar was not copied to the target directory of spark.
That was probably the reason why the translation update was not visible in the new spark builds.

committed to trunk

spark_i18n_pl.properties updated for recent changes in the SVN

Closing for now as there weren't new changes with new GUI text.

Updated spark_i18n_pl.properties, provided by Martini26

the ticket should be closed when releasing the final version, as there could be new changes to the translation before that point