RelaxedStacked version via cat

[creichen]

• Adds tools/cat.jar
• Updates tools/jastadd2.jar to the idriss--dnc-squashed branch version of JastAdd2
• Updates build script to expect and use cache-config.csv file
• Adds script to build cache-config.csv file
• Note: I have not validated the performance behaviour
• Note: Will require a non-DNC build before ./run-cat.sh can produce meaningful output.

Not intended for merging yet; somene with Gradle skills will need to productionise all this. The following manual steps should hopefully work:

# Prevent DNC build from failing by providing dummy cache configuration:
touch ./cache-config.csv
# Build with zero NonCircular attributes (since cache-config.csv is empty):
./gradlew clean jar test
# Generate proper cache-config.csv:
./run-cat.sh
# Build with proper cache-config.csv:
./gradlew clean jar test