Fix interval select display

These commits fix :

• IntervalSelect not updating when adding or removing a trace
• filenames being too short which could lead to confusion when opening files with the same name

src/core/Core.cpp

@@ -370,7 +370,8 @@ Trace *Core::build_trace(const std::string &filename, bool is_state_splitting) {
         return nullptr;
     }
 
-    Trace *trace = new Trace(filename);
+    QFileInfo filepath(QString::fromStdString(filename));
+    Trace *trace = new Trace(filepath.absoluteFilePath().toStdString());
 
 #if defined(USE_ITC) && defined(BOOST_SERIALIZE)
     if (Info::Splitter::path.empty())