Remove the javac arguments files from the jar files

When a Maven project is built with the fork mode enabled for the maven-compiler.plugin, two extra files containing non reproducible elements are generated in the output directory and subsequently packaged in the jar. These files are:

• javac.sh: an executable script that could be run to recompile the project. It captures the build path.
• org.codehaus.plexus.compiler.javac.JavacCompiler[0-9]+arguments: contains the compiler arguments. The file name uses a random value.

These files can be safely removed.

src:fop is an example of package affected by this issue, it produces libfop-java with several jar files (/usr/share/java/fop-core.jar, fop-events.jar, fop-util.jar, etc) containing these files.