ui: Added custom trail dialog (issue #249)

* open custom trail dialg via button in top of trail controls
* search from symbol to symbol or all referenced/referencing of symbol
* define search depth with slider
* define horizontal/vertical layout
* define node and edge types
* renamed depth graph to trail in graph ui
* added custom trail UI tests

fortune cookie message = A happy surprise is waiting for you.

src/lib_gui/qt/window/QtMainWindow.cpp

@@ -40,6 +40,7 @@
 #include "MessageBookmarkBrowse.h"
 #include "MessageBookmarkCreate.h"
 #include "MessageCodeReference.h"
+#include "MessageCustomTrailShow.h"
 #include "MessageFind.h"
 #include "MessageIndexingShowDialog.h"
 #include "MessageLoadProject.h"
@@ -755,6 +756,11 @@ void QtMainWindow::codeLocalReferenceNext()
 	MessageCodeReference(MessageCodeReference::REFERENCE_NEXT, true).dispatch();
 }
 
+void QtMainWindow::customTrail()
+{
+	MessageCustomTrailShow().dispatch();
+}
+
 void QtMainWindow::overview()
 {
 	MessageActivateAll().dispatch();
@@ -963,6 +969,10 @@ void QtMainWindow::setupEditMenu()
 
 	menu->addSeparator();
 
+	menu->addAction(tr("Custom Trail..."), this, &QtMainWindow::customTrail, QKeySequence(Qt::CTRL + Qt::Key_L));
+
+	menu->addSeparator();
+
 	menu->addAction(tr("&To overview"), this, &QtMainWindow::overview, QKeySequence::MoveToStartOfDocument);
 
 	menu->addSeparator();