Improving PL/Java build system

PL/Java is an open source extension PostgreSQL that allows stored procedures, triggers and functions to be written in Java. PL/Java ‘s build system utilizes Maven. PL/Java is most written in Java and C but also uses some bits of JavaScript. The project utilizes nar-maven-plugin to build native code. Overall, the build system is intricately woven and works well. At the same time, many issues in the PL/Java GitHub repository bear testimony to its drawbacks. This project aims to make the build system more robust and ease the development process.