fix deprecated boost function (#604)

Author: marcschefer

SEBenchmarks/src/program/BenchBackgroundModel.cpp

@@ -80,7 +80,7 @@ class BenchBackgroundModel : public Elements::Program {
     if (i != args.end())
       return i->second.as<std::string>();
     auto input = boost::filesystem::path(m_detection_config.getDetectionImagePath());
-    auto basename = input.leaf();
+    auto basename = input.filename();
     while (!basename.extension().empty())
       basename = basename.stem();
     auto algo = args.at("algorithm").as<std::string>();