add binary literals

tests/t005.cxl

@@ -0,0 +1,8 @@
+#include <stdio.h>
+
+int main(int argc, char * argv[])
+{
+    printf("%d;", 0b01u | 0b10u);
+    printf("%d;", 0x100 - 0b100000000);
+    printf("\n");
+}

tests/t005.x

@@ -0,0 +1 @@
+3;0;