Download rxtx-rebundled JAR file with all dependencies

rxtx-rebundled is a slightly modified version of the original rxtx 2.1-7r2. The only difference is: 1) It's a working mavenized library 2) There's just one JAR required. Nothing else. The native libs are bundled with the jar-file. 3) You don't have to care about "java.library.path". This version will on startup extract the correct native libs to system temp folder and loads them automatically. When JVM terminates, temp files will be removed.