Added SystemInfo and FileSystems to query system and file system information, respectively.

src/main/cpp/generic.cpp

@@ -17,5 +17,5 @@ void mark_failed_with_code(JNIEnv *env, const char* message, int error_code, job
 
 JNIEXPORT jint JNICALL
 Java_net_rubygrapefruit_platform_internal_jni_NativeLibraryFunctions_getVersion(JNIEnv *env, jclass target) {
-    return 4;
+    return 5;
 }