/* UTF-8 encoding
00000000-01111111 00-7F US-ASCII (single byte)
10000000-10111111 80-BF Second, third, or fourth byte of a multi-byte sequence
11000000-11011111 C0-DF Start of 2-byte sequence
11100000-11101111 E0-EF Start of 3-byte sequence
11110000-11110100 F0-F4 Start of 4-byte sequence
*/