REORG: http: move HTTP rules parsing to http_rules.c

These ones are mostly called from cfgparse.c for the parsing and do
not depend on the HTTP representation. The functions's prototypes
were moved to proto/http_rules.h, making this file work exactly like
tcp_rules. Ideally we should stop calling these functions directly
from cfgparse and register keywords, but there are a few cases where
that wouldn't work (stats http-request) so it's probably not worth
trying to go this far.
diff --git a/Makefile b/Makefile
index 3140a4a..5cf4ce0 100644
--- a/Makefile
+++ b/Makefile
@@ -895,7 +895,7 @@
        src/protocol.o src/lru.o src/hdr_idx.o src/hpack-huff.o          \
        src/mailers.o src/h2.o src/base64.o src/hash.o src/http.o	\
        src/http_acl.o src/http_fetch.o src/http_conv.o src/http_act.o   \
-       src/proto_sockpair.o
+       src/http_rules.o src/proto_sockpair.o
 
 EBTREE_OBJS = $(EBTREE_DIR)/ebtree.o $(EBTREE_DIR)/eb32sctree.o \
               $(EBTREE_DIR)/eb32tree.o $(EBTREE_DIR)/eb64tree.o \