(svn r7331) - Codechange: Rename all memory pool macro's and types to "old pool", so the new pool implementation can be committed alongside it.

- Codechange: Rename pool.[ch] to oldpool.[ch].

Makefile

@@ -741,6 +741,7 @@ SRCS += newgrf_text.c
 SRCS += news_gui.c
 SRCS += npf.c
 SRCS += oldloader.c
+SRCS += oldpool.c
 SRCS += openttd.c
 SRCS += order_cmd.c
 SRCS += order_gui.c
@@ -748,7 +749,6 @@ SRCS += os_timer.c
 SRCS += pathfind.c
 SRCS += player_gui.c
 SRCS += players.c
-SRCS += pool.c
 SRCS += queue.c
 SRCS += rail.c
 SRCS += rail_cmd.c