BUG/MEDIUM: stick-tables: complete the latest fix about store-responses

The commit 37e340c (BUG/MEDIUM: stick: completely remove the unused flag
from the store entries) was incomplete. We also need to ensure that only
the first store-response for a table is applied and that it may coexist
with a possible store-request that was already done on this table.

This patch with the previous one should be backported to 1.4.
BUG/MEDIUM: pattern: Pattern node has type of "struct pat_idx_elt" in place of "struct eb_node"

The free() function must free the "struct pat_idx_elt".

This bug was introduced by commit ed66c29 (REORG: acl/pattern: extract
pattern matching from the acl file and create pattern.c), no backport
is needed.