A function macro named E clashes with internal boost definitions.  Rearrange
the order of header inclusion so that affected boost headers are included
before monotone defines the macro.

Also, stop bundling boost/circular_buffer, which is available in current
versions of boost. From Fedora.

Index: src/commands.hh
--- src/commands.hh.orig
+++ src/commands.hh
@@ -10,8 +10,8 @@
 #ifndef __COMMANDS_HH__
 #define __COMMANDS_HH__
 
-#include "vector.hh"
 #include "options.hh"
+#include "vector.hh"
 class app_state;
 class utf8;