Reload colors in reset

Colors definition can be changed using a OSC sequence, so
we have to reload them if we want be sure all the colors
are the correct.

Could be desirable free the colors allocated due to rgb
colors and inverse colors (XftColorAllocValues in xdraws),
but it is impossible due we use the same structure for all
of them.

st.c

@@ -2428,6 +2428,7 @@ tputc(char *c, int len) {
 				treset();
 				term.esc = 0;
 				xresettitle();
+				xloadcols();
 				break;
 			case '=': /* DECPAM -- Application keypad */
 				term.mode |= MODE_APPKEYPAD;
@@ -2589,6 +2590,13 @@ void
 xloadcols(void) {
 	int i, r, g, b;
 	XRenderColor color = { .alpha = 0xffff };
+	static bool loaded;
+	Colour *cp;
+
+	if(loaded) {
+		for (cp = dc.col; cp < dc.col + LEN(dc.col); ++cp)
+			XftColorFree(xw.dpy, xw.vis, xw.cmap, cp);
+	}
 
 	/* load colors [0-15] colors and [256-LEN(colorname)[ (config.h) */
 	for(i = 0; i < LEN(colorname); i++) {
@@ -2621,6 +2629,7 @@ xloadcols(void) {
 			die("Could not allocate color %d\n", i);
 		}
 	}
+	loaded = true;
 }
 
 int