Replace p_context_init() with p_context_new()/p_context_delete()

spec/test_starting_rules.d

@@ -10,20 +10,20 @@ int main()
 unittest
 {
     string input = "bbbb";
-    p_context_t context;
-    p_context_init(&context, input);
-    assert(p_parse(&context) == P_SUCCESS);
-    int result = p_result(&context);
+    p_context_t * context;
+    context = p_context_new(input);
+    assert(p_parse(context) == P_SUCCESS);
+    int result = p_result(context);
     assert(result == 8);
 
-    p_context_init(&context, input);
-    assert(p_parse_Bs(&context) == P_SUCCESS);
-    result = p_result_Bs(&context);
+    context = p_context_new(input);
+    assert(p_parse_Bs(context) == P_SUCCESS);
+    result = p_result_Bs(context);
     assert(result == 8);
 
     input = "c";
-    p_context_init(&context, input);
-    assert(p_parse_R(&context) == P_SUCCESS);
-    result = p_result_R(&context);
+    context = p_context_new(input);
+    assert(p_parse_R(context) == P_SUCCESS);
+    result = p_result_R(context);
     assert(result == 3);
 }