Add comment processing, add a comment to factorial.sy to test it out

Signed-off-by: Alek Ratzloff <alekratz@gmail.com>

src/syn/parser.pest

@@ -1,10 +1,11 @@
-WHITESPACE = _{ " " | "\r" | "\t" | "\n" }
+newline = _{ "\n" | "\r\n" }
+WHITESPACE = _{ newline | " " | "\r" | "\t"}
+COMMENT = _{ "#" ~ (!newline ~ ANY)* }
 
 int = @{ ASCII_DIGIT+ }
 float = @{ ASCII_DIGIT+ ~ "." ~ ASCII_DIGIT+ ~ ("e" ~ ("+" | "-")? ~ ASCII_DIGIT+)? }
 word_char = @{ ASCII_ALPHA | "_" | "?" | "-" | "+" | "*" | "/" | "=" | "@" | "$" | "%" | "^" | "&" | "|" | "~" }
 word = @{ word_char+ }
-// meta = ${ "%" ~ word }
 str = @{
     "\"" ~
     (