get jruby version and mode from Gemfile
Enable debuggning
dont leak output from trying to run rake asssets:precomple
Remove bundle cache before copying back the new
move argument order in JRUBY_OPTS
set the ruby mode in bin/release, from Gemfile
export JRUBY_OPTS
Lower memory usage and better startup time
relase scripts starts in BUILD_DIR
remove previous jruby installations if any