otioload: Add simple dialog to change settings

Adds a table of sequences in the OTIO file and allows the settings to
be changed. The dialog takes a list of sequences and relies on each
OTIO timeline having a unique name.

The dialog has to be called from the main thread so there is a wrapper
function in Core.

app/core.cpp

@@ -43,6 +43,7 @@
 #include "dialog/autorecovery/autorecoverydialog.h"
 #include "dialog/export/export.h"
 #include "dialog/footagerelink/footagerelinkdialog.h"
+#include "dialog/otioproperties/otiopropertiesdialog.h"
 #include "dialog/sequence/sequence.h"
 #include "dialog/task/task.h"
 #include "dialog/preferences/preferences.h"
@@ -379,6 +380,12 @@ void Core::DialogExportShow()
   }
 }
 
+void Core::DialogImportOTIOShow(QList<Sequence*> sequences) {
+  Project* active_project = GetActiveProject();
+  OTIOPropertiesDialog opd(sequences, active_project);
+  opd.exec();
+}
+
 void Core::CreateNewFolder()
 {
   // Locate the most recently focused Project panel (assume that's the panel the user wants to import into)