Support for vuln-regex-detector

[davisjam]

• Maven tweaks to build jar, not just compile
• Input and output changes to match the vuln-regex-detector spec
• Shift some outputs from stdout to stderr

These changes look sufficient for use with vuln-regex-detector, and I can add a ReScue driver there after they are merged.

Let me know if you want any changes!

[davisjam]

After #5 is merged, we should add the new build instructions.

They are:

mvn clean
mvn compile
mvn package

@2bdenny You may want to change the build directory and jar file. At the moment it goes to target/ReScue-1.0.jar.