Use a macro to determine the size of arrays

Use following macro instead of "sizeof(x) / sizeof(x[0])" everywhere:

    #define ARRAY_SIZE(x) (sizeof(x) / sizeof((x)[0]))

Signed-off-by: Lukas Fleischer <calcurse@cryptocrack.de>

src/utf8.c

@@ -307,7 +307,7 @@ int utf8_width(char *s)
 	}
 
 	low = 0;
-	high = sizeof(utf8_widthtab) / sizeof(utf8_widthtab[0]);
+	high = ARRAY_SIZE(utf8_widthtab);
 	do {
 		cur = (low + high) / 2;
 		if (val >= utf8_widthtab[cur].min) {