Original eclipse setup used the jar command from the system path
which resulted in different behavior on different systems. This
change modifies the build target to use the jar command provided
by bazel: @local_jdk//:bin/jar
Simple python script to generate the .project and .classpath files
for eclipse. The script bundles all jar dependencies into a single
jar file, collects all auto-generated java files into a single
source folder and adds them to the eclipse classpath.