symbol-name symbol => name
symbol—a symbol.
name—a string.
symbol-name returns the name of symbol.
The consequences are undefined if name is ever modified.
(symbol-name 'temp) => "TEMP"
(symbol-name :start) => "START"
(symbol-name (gensym)) => "G1234" ;for example
Should signal an error of type type-error if symbol is not a symbol.