Fix some memory leaks

Some elements of modules and boards were not deleted, so memory
was being leaked on some library loads and single-instance
pcbnew usage.

kicad/kicad_manager_frame.cpp

@@ -165,6 +165,13 @@ KICAD_MANAGER_FRAME::KICAD_MANAGER_FRAME( wxWindow* parent, const wxString& titl
 
 KICAD_MANAGER_FRAME::~KICAD_MANAGER_FRAME()
 {
+    // Ensure there are no active tools
+    if( m_toolManager )
+        m_toolManager->DeactivateTool();
+
+    delete m_actions;
+    delete m_toolManager;
+
     m_auimgr.UnInit();
 }
 

pcbnew/class_board.cpp

@@ -146,9 +146,28 @@ BOARD::~BOARD()
         Delete( area_to_remove );
     }
 
+    // Clean up the owned elements
     DeleteMARKERs();
     DeleteZONEOutlines();
 
+    // Delete the modules
+    for( auto m : m_modules )
+        delete m;
+
+    m_modules.clear();
+
+    // Delete the tracks
+    for( auto t : m_tracks )
+        delete t;
+
+    m_tracks.clear();
+
+    // Delete the drawings
+    for (auto d : m_drawings )
+        delete d;
+
+    m_drawings.clear();
+
     delete m_CurrentZoneContour;
     m_CurrentZoneContour = NULL;
 }

pcbnew/class_module.cpp

@@ -142,9 +142,20 @@ MODULE::MODULE( const MODULE& aModule ) :
 
 MODULE::~MODULE()
 {
+    // Clean up the owned elements
     delete m_Reference;
     delete m_Value;
     delete m_initial_comments;
+
+    for( auto p : m_pads )
+        delete p;
+
+    m_pads.clear();
+
+    for( auto d : m_drawings )
+        delete d;
+
+    m_drawings.clear();
 }