Fix two Visual Studio compiler warnings

+ fix trailing whitespace (fluid)

fluid/Fl_Group_Type.cxx

@@ -328,7 +328,7 @@ void Fl_Flex_Type::change_subtype_to(int n) {
     if (fw<=nc) fw = nc; // avoid division by zero
     int fh = f->h()-dh-tm-bm-(nc*gap);
     if (fh<=nc) fh = nc; // avoid division by zero
-    
+
     if (f->type()==Fl_Flex::HORIZONTAL && n==Fl_Flex::VERTICAL) {
       float scl = (float)fh/(float)fw;
       for (int i=0; i<nc; i++) {

src/Fl_SVG_Image.cxx

@@ -130,7 +130,7 @@ static char *svg_inflate(gzFile gzf, // can be a file or the read end of a pipe
       break;
     }
 
-    l = gzread(gzf, p, size);
+    l = gzread(gzf, p, (unsigned int)size);
     if (l > 0) {
       p += l; *p = 0;
     }

src/Fl_Text_Display.cxx

@@ -4153,7 +4153,7 @@ int Fl_Text_Display::handle(int event) {
       if (dragType==DRAG_START_DND) {
         if (!Fl::event_is_click() && Fl::dnd_text_ops()) {
           const char* copy = buffer()->selection_text();
-          Fl::copy(copy, strlen(copy));
+          Fl::copy(copy, (int)strlen(copy));
           Fl::screen_driver()->dnd(1);
           free((void*)copy);
         }