Finish out the basic primitives along with testing infra for both parsing and evalaution, with some slick Into<> impls to make Rust values Kraken values, which is esp useful for testing

kr/src/grammar.lalrpop

@@ -20,8 +20,8 @@ match {
     ")",
     ".",
     "'",
-    r"[0-9]+"                    => NUM,
-	r"[a-zA-Z+*/_=-][\w+*/=_-]*" => SYM,
-	r"(;[^\n]*\n)|\s+"           => { }
+    r"[0-9]+"                              => NUM,
+    r"[a-zA-Z+*/_=?%&|^-][\w+*/=_?%&|^-]*" => SYM,
+    r"(;[^\n]*\n)|\s+"                     => { }
 }