Automatic decoding of supported literals in REPL

Automatic decoding & display of string, number, and list types in REPL.
General updates to README, style, and comments.

src/Lexer.hs

@@ -45,7 +45,7 @@ stringLiteral = do
   if null content
     then fail "Empty string literals are not allowed"
     else do
-      char '"'
+      char '"' --"
       return (LStringLiteral content)
 
 assign :: Lexer LToken