* 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

Introduced Sympa::Tools::Text::slurp() to slurp text file applying Unicode sanitization and normalization. Note: Though Unicode::Normalize and Unicode::UTF8 are optional now, they would be mandatory in the future.

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.

Spurious error message during upgrade from a version prior to 6.2b.1, if the directory /etc/sympa/web_tt2 does not exist.

This will fix several bugs due to confusion with function and parameter.

Fixed by updating the table not according to list membership of user in user_exclusion field; removing the rows with the name of list no longer exists.

[change] Data sources: outdated users will be expired only when all data sources of the list has succeeded inclusion.
By this change, if there are data sources with nosync_time_ranges set, deletion of outdated users can be delayed 24 hours at most.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.

Copying timestamp of original css.tt2 confuses browser cache.  Older timestamp of css.tt2 should be avoided by measures in release and install process.

[change] Like the other parameters, defaults of list scenarios would be specified by corresponding robot/site parameters, instead of creating file or link named "*.default".
Defaults by older manner will be detected and written in sympa.conf/robot.conf during upgrading process.

Fixes:

  - Message footer/header files of domain/site default are put in `mail_tt2` subdirectories while those of list config are not.
    Fixed by put all of them in consistent location without intermediate directories (See also Notes below).
  - Entries for header/footer files in `edit_list.conf` were ignored.

Changes:

  - File names themselves of header/footer were changed:
    `message_header`, `message_header.mime` etc.
    This is due to concideration about conflict between files and directories with domain names (See also Notes below).
  - Header/footer files with `.mime` extension:
    Previously, files with this extension were always preferred, then files without extension were used.  This behavior has not been documented.
    Now files with extension will be searched only in case `footer_type` is `mime`.  Files without extension will be searched in both cases.

Notes:

  - Files with older names/paths in list/domain/site config directories will be copied to new location during upgrading process.
  - Template files with old names in families (`message.header.tt2` etc.) will be used as before and will be copied to new location during instantiation. If files with new names (`message_header.tt2` etc.) will be preferred, if they will be added.

Known bug:

  - There are no web UI to edit global footer (`message_global_footer`).

  - Write out initial permanent owners/moderators in <role>.dump files.
  - And, if list is not closed, import owners/moderators from those files into database.

Various places in both documentation and default emails to admins/moderators
use he/him/his to refer to generic users of unknown gender. This commit
changes all generic uses of male pronouns to use singular they/them/their.
It also changes "his/her" to "their", but leaves "he or she" unchanged due
to less trivial conjugation issues.  NEWS, AUTHORS.md, and OChangeLog are
unchanged.

It was gone years ago.

[change] Move task files to task/ subdirectories. Previously list_task_models/ and global_task_models/ directories were used.  Task files in older directories will be automatically copied to new places during upgrading process.