Improve `Ronin::Support::Encoding::SQL`

[postmodern]

• Only escape/unescape ' as '' and vice-versa.
• Escape " as \".
• Encode each character as CHAR(XX)||CHAR(XX)||....
• Handle unescaping/decoding ||CHAR(XX)|| in Strings.
• Handle unescaping/decoding "foo"||"bar" strings.
• Add .escape_byte and .encode_byte methods.

[postmodern]

unescape will need to be re-implemented using StringScanner to separate quoted strings from ||CHAR(XX)||.