Revision 1716122

Extend the config support to include listeners as well. Rename the
create functions to make it clear they create a new config instance.

* config_store.c
  (conn_key_for_listener): New function.
  (serf__config_store_get_config): Split into...
  (serf__config_store_create_ctx_config): ... this and...
  (serf__config_store_create_conn_config): ... this function.
  (serf__config_store_get_client_config): Rename to...
  (serf__config_store_create_client_config): ... this.
  (serf__config_store_create_listener_config): New function.

* context.c
  (serf_context_create_ex): Update caller.

* incoming.c
  (serf_incoming_create2): Update caller.
  (serf_listener_create): Allocate listener in its own pool.
    Initialize config.

* outgoing.c
  (serf_connection_create2): Update caller.

* serf_private.h
  (serf__config_store_get_config): Rename to...
  (serf__config_store_create_conn_config): ... this.
  (serf__config_store_get_client_config): Rename to...
  (serf__config_store_create_client_config): ... this.
  (serf__config_store_create_listener_config,
   serf__config_store_create_ctx_config): New function.

* test/test_internal.c
  (test_config_store_per_context,
   test_config_store_per_connection_different_host,
   test_config_store_per_connection_same_host,
   test_config_store_error_handling,
   test_config_store_remove_objects): Update caller.