[MAJOR] huge rework of the HTTP request FSM

The HTTP parser has been rewritten for better compliance to RFC2616.
The same parser is now usable for both requests and responses, and
it now supports HTTP/0.9 as well as multi-line headers. It has also
been improved for speed ; a typicial HTTP request is parsed in about
2 microseconds on a 1 GHz processor.

The monitor-uri check has been moved so that the requests are not
logged. The httpclose option now tries to change as little as
possible in the request, and does not affect the first header if
it is already set to 'close'. HTTP/0.9 requests are converted to
HTTP/1.0 before being forwarded.

Headers and request transformations are now distinct. The headers
list is updated after each insertion/removal/transformation. The
request is re-parsed and checked after each transformation. It is
not possible anymore to remove a request, and requests which lead
to invalid request lines are now rejected.
diff --git a/src/session.c b/src/session.c
index 5372b7d..3e1cc61 100644
--- a/src/session.c
+++ b/src/session.c
@@ -21,6 +21,7 @@
 #include <types/proxy.h>
 #include <types/server.h>
 
+#include <proto/hdr_idx.h>
 #include <proto/session.h>
 #include <proto/queue.h>