Add time zone support to Notifications

Current Situation

• The JS7 stores dates in UTC in its database.
• The JOC Cockpit daemon/service is operated in the UTC time zone.
• When notifications are sent, for example by mail in case of job errors, then dates are accordingly stated in UTC.

Desired Behavior

• Users wish to receive notifications with dates in their desired time zone.
• The configuration of notifications should allow to specify the time zone
  • at Message element level: the time zone is used for any occurrence of the message
  • at NotificationMonitors level: the time zone is used specifically for notifications configured with this element

Maintainer Note

• Time zone configuration.
  • Introduction of a new attribute time_zone for the following configuration elements:
    1. Fragments/MessageFragments@time_zone
       • Default: Etc/UTC
       • Scope: the time zone is used for all notifications.
    2. Fragments/MessageFragments/Message@time_zone
       • Scope: overrides 1. configuration for any occurrence of the specific message.
    3. Notifications/Notification/NotificationMonitors/<CommandFragmentRef|MailFragmentRef|JMSFragmentRef|NSCAFragmentRef>@time_zone
       • Scope: overrides 1. and 2. configurations for the specific monitor.
• Date formatting.
  • Using time zone offsets.
    • Examples:
      • 2022-07-05T12:00:00+0000
      • 2022-07-05T10:00:00-0200
      • 2022-07-05T14:00:00+0200
• Time zone variable.
  • Introduction of a new notification Common Variable: MON_TIME_ZONE

Workaround for Command elements

• If a Command element is used, for example to write notifications to a file or to forward to a system monitor then for operating systems with GNU Date the following command can be used to convert the UTC time of a monitor variable:

• MON_O_START_TIME=$(env TZ='Asia/Tokyo' date --date="${MON_O_START_TIME}Z")