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

A few includes had to be added, namely list-t.h in the type file and
types/proxy.h in the proto file. actions.h was including http-htx.h
but didn't need it so it was dropped.
diff --git a/src/http_act.c b/src/http_act.c
index 165cae2..cba3c79 100644
--- a/src/http_act.c
+++ b/src/http_act.c
@@ -20,6 +20,7 @@
 #include <common/cfgparse.h>
 #include <haproxy/chunk.h>
 #include <haproxy/http.h>
+#include <haproxy/http_htx.h>
 #include <haproxy/pool.h>
 #include <haproxy/regex.h>
 #include <haproxy/tools.h>
@@ -33,7 +34,6 @@
 #include <proto/arg.h>
 #include <proto/action.h>
 #include <proto/http_rules.h>
-#include <proto/http_htx.h>
 #include <proto/log.h>
 #include <proto/http_ana.h>
 #include <proto/pattern.h>