- Renamed parameter "merge_feature" to "personalization_feature"

Limit personalization: Only when posted from WWSympa, entire text will be converted. Otherwise only footer/header will be converted.

<sympa-request> address should not be forwarded to any functions of Sympa.  To avoid mail loop by such misconfiguration, discard messages bound for this address.

* review: Won't process sync_include in advance so that processing will be faster.

* Refactoring. Sympa::List::on_the_fly_sync_include() was removed. Instead, "include" request handler had "delay" option.

* Remove unused "last_sync" cache entries.  "last_change" entries remain.

* sync_include will no longer be invoked during Sympa::List->new():
  - No owner defined in a list is no longer treated as error_config.
  - Instead, if no owner defined,
     - If possible, discard incoming message and send back DSN to original sender,
     - or, notifications to owners will be redirected to listmaster(s).

* Refactoring: Remove unused functions

* Small refactoring: mail_tt2/listeditor_notification.tt2 is no longer used.

* Clarify log messages and DSN about undefined owner/editor/listmaster

Fixes #820: If a "reject" action in a scenario does not have "quiet" modifier, and the incoming message does not have spam flag, rejection notice will be sent back.

A note:
Now create_list, create_automatic_list & update_automatic_list Request handlers won't take "listname" as an top-level parameter, but it must be included in an item of "parameters" parameter.

Archive directories of any lists may be created even if archive is unavailable, or Sympa may crash (#736)

[bug] task_manager.pl dies when the list no longer exist when some command such as sync_include was executed.
Fixed by checking if target list exists.

Fix #634

[change] Data sources: outdated users will be expired only when all data sources of the list has succeeded inclusion.
By this change, if there are data sources with nosync_time_ranges set, deletion of outdated users can be delayed 24 hours at most.
[change] Database schema: included_* and include_sources_* in subscriber_table and admin_table were deprecated.  inclusion_* fields will be used instead.