REORG: include: move server.h to haproxy/server{,-t}.h

extern struct dict server_name_dict was moved from the type file to the
main file. A handful of inlined functions were moved at the bottom of
the file. Call places were updated to use server-t.h when relevant, or
to simply drop the entry when not needed.
diff --git a/include/haproxy/backend.h b/include/haproxy/backend.h
index 6662d59..5f6acaa 100644
--- a/include/haproxy/backend.h
+++ b/include/haproxy/backend.h
@@ -25,8 +25,8 @@
 #include <haproxy/backend-t.h>
 #include <haproxy/api.h>
 #include <haproxy/proxy-t.h>
+#include <haproxy/server-t.h>
 #include <haproxy/time.h>
-#include <types/server.h>
 #include <types/stream.h>
 
 int assign_server(struct stream *s);