Remove := operator and fix & usage.

unittests/ref_equal.chai

@@ -1,5 +0,0 @@
-auto i = 3
-auto j := i
-j = 4
-
-assert_equal(4, i)

unittests/reflection_test.chai

@@ -1,14 +1,14 @@
 load_module("reflection")
-auto parser := ChaiScript_Parser()
+auto& parser = ChaiScript_Parser()
 auto parse_success = parser.parse("3 + 4", "INPUT")
-auto a := parser.ast()
+auto& a = parser.ast()
 
 assert_equal(eval(a), 7)
 
-auto childs := a.children.front().children
-auto node := childs[0]
+auto& childs = a.children.front().children
+auto& node = childs[0]
 
-auto parser2 := ChaiScript_Parser()
+auto& parser2 = ChaiScript_Parser()
 parser2.parse("9", "INPUT")
 
 
@@ -30,7 +30,7 @@ assert_equal(false, `+`.has_parse_tree());
 
 assert_throws("Function does not have a parse tree", fun() { `+`.get_parse_tree(); } );
 
-auto parsetree := my_fun.get_parse_tree();
+auto& parsetree = my_fun.get_parse_tree();
 
 assert_equal(1, eval(parsetree));