As described in [[UTF-8]] and in [[wp:UTF-8|Wikipedia]], UTF-8 is a popular encoding of (multi-byte) [[Unicode]] code-points into eight-bit octets.

The goal of this task is to write a encoder that takes a unicode code-point (an integer representing a unicode character) and returns a sequence of 1–4 bytes representing that character in the UTF-8 encoding. 

Then you have to write the corresponding decoder that takes a sequence of 1–4 UTF-8 encoded bytes and return the corresponding unicode character.

Demonstrate the functionality of your encoder and decoder on the following five characters:

<pre>
Character   Name                                  Unicode    UTF-8 encoding (hex)
---------------------------------------------------------------------------------
A           LATIN CAPITAL LETTER A                U+0041     41
ö           LATIN SMALL LETTER O WITH DIAERESIS   U+00F6     C3 B6
Ж           CYRILLIC CAPITAL LETTER ZHE           U+0416     D0 96
€           EURO SIGN                             U+20AC     E2 82 AC
𝄞           MUSICAL SYMBOL G CLEF                 U+1D11E    F0 9D 84 9E
</pre>

Provided below is a reference implementation in Common Lisp.

