Add example for Unicode Code point literal > 255

Only Basic Latin and Latin-1 Supplement code points fit into a single
byte.

exercises/059_integers.zig

@@ -6,7 +6,8 @@
 //     const a2: u8 = 0x41;      // hexadecimal
 //     const a3: u8 = 0o101;     // octal
 //     const a4: u8 = 0b1000001; // binary
-//     const a5: u8 = 'A';       // UTF-8 code point literal
+//     const a5: u8 = 'A';       // ASCII code point literal
+//     const a6: u16 = 'Ȁ';      // Unicode code points can take up to 21 bits
 //
 // You can also place underscores in numbers to aid readability:
 //

patches/patches/059_integers.patch

@@ -1,4 +1,4 @@
-22,24c22,24
+23,25c23,25
 <         0o131, // octal
 <         0b1101000, // binary
 <         0x66, // hex