Fix color behavior on some terminals.

Fixes #635.

CRT.c

@@ -37,6 +37,7 @@ in the source distribution for its full text.
 #define White COLOR_WHITE
 
 #define ColorPairGrayBlack ColorPair(Magenta,Magenta)
+#define ColorIndexGrayBlack ColorIndex(Magenta,Magenta)
 
 #define KEY_WHEELUP KEY_F(20)
 #define KEY_WHEELDOWN KEY_F(21)
@@ -713,22 +714,23 @@ void CRT_enableDelay() {
 
 void CRT_setColors(int colorScheme) {
    CRT_colorScheme = colorScheme;
-   if (colorScheme == COLORSCHEME_BLACKNIGHT) {
-      for (int i = 0; i < 8; i++)
-         for (int j = 0; j < 8; j++) {
-            if (ColorIndex(i,j) != ColorIndex(Magenta,Magenta)) {
-               init_pair(ColorIndex(i,j), i, j);
-            }
-         }
-      init_pair(ColorIndex(Magenta,Magenta), 8, 0);
-   } else {
-      for (int i = 0; i < 8; i++) 
-         for (int j = 0; j < 8; j++) {
-            if (ColorIndex(i,j) != ColorIndex(Magenta,Magenta)) {
-               init_pair(ColorIndex(i,j), i, (j==0?-1:j));
-            }
+
+   for (int i = 0; i < 8; i++) {
+      for (int j = 0; j < 8; j++) {
+         if (ColorIndex(i,j) != ColorPairGrayBlack) {
+            int bg = (colorScheme != COLORSCHEME_BLACKNIGHT)
+                     ? (j==0 ? -1 : j)
+                     : j;
+            init_pair(ColorIndex(i,j), i, bg);
          }
-      init_pair(ColorIndex(Magenta,Magenta), 8, -1);
+      }
    }
+
+   int grayBlackFg = COLORS > 8 ? 8 : 0;
+   int grayBlackBg = (colorScheme != COLORSCHEME_BLACKNIGHT)
+                     ? -1
+                     : 0;
+   init_pair(ColorIndexGrayBlack, grayBlackFg, grayBlackBg);
+
    CRT_colors = CRT_colorSchemes[colorScheme];
 }

CRT.h

@@ -26,6 +26,7 @@ in the source distribution for its full text.
 #define White COLOR_WHITE
 
 #define ColorPairGrayBlack ColorPair(Magenta,Magenta)
+#define ColorIndexGrayBlack ColorIndex(Magenta,Magenta)
 
 #define KEY_WHEELUP KEY_F(20)
 #define KEY_WHEELDOWN KEY_F(21)

ColorsPanel.c

@@ -78,6 +78,7 @@ static HandlerResult ColorsPanel_eventHandler(Panel* super, int ch) {
       this->settings->changed = true;
       const Header* header = this->scr->header;
       CRT_setColors(mark);
+      clear();
       Panel* menu = (Panel*) Vector_get(this->scr->panels, 0);
       Header_draw(header);
       RichString_setAttr(&(super->header), CRT_colors[PANEL_HEADER_FOCUS]);