Various smaller changes. Updated proto files. Updated dependencies.
diff --git a/src/if_ruby.c b/src/if_ruby.c
index 2ee329b..8003d4c 100644
--- a/src/if_ruby.c
+++ b/src/if_ruby.c
@@ -170,7 +170,10 @@
#define rb_str_cat dll_rb_str_cat
#define rb_str_concat dll_rb_str_concat
#define rb_str_new dll_rb_str_new
-#define rb_str_new2 dll_rb_str_new2
+/* Ruby may also define rb_str_new2. */
+#ifndef rb_str_new2
+# define rb_str_new2 dll_rb_str_new2
+#endif
#if defined(DYNAMIC_RUBY_VER) && DYNAMIC_RUBY_VER >= 18
# define rb_string_value_ptr dll_rb_string_value_ptr
# define rb_float_new dll_rb_float_new