We need to show the stream-specific notification settings only in
user notification settings and not for realm-level default settings.
This commit is a prep commit and adds a condition to make sure that
stream-specific settings are shown only for user-settings.
This commit adds prefix paramter with value "user_" to the
settings_checkbox and notification_settings_checkboxes references
in notification_settings.hbs such that ids are unique when we use
notification_settings.hbs for realm-level settings UI.
This commit creates a new template user_notification_settings.hbs
for user notification settings and notification_settings.hbs will
be used as a common template for user-level and realm-level
settings.
Sahil Batra