Created key must always be looked for as it is not assigned to the
passed in null key.
Delete local context and loopback passphrase provider.
Parameter expires was ignored in CreateKeyWithEngineDefaultAlgo.
This is a trade-off.
When the calendar of the WDateEdit is clicked, widget PopupExpiryTime gets hidden, forcing to show it again.
If PopupExpiryTime::setTransient is false, it will obviously persist, until explicitly hidden with the Close button. Not satisfactory to change key selection while it is visible, nor to do other tasks like changing certification trust level, certifying uids.... whatever.
Forcing its persistence while playing with many events has not been successful, and quite ugly.
A private key should be editable to Unknown or Ultimate levels only.
A public key should be editable to all levels except Ultimate.
Undefined level is excluded for both public and private keys.
The public WTreeTableNode may list private keys if the user does not manage
these private keys. Inform of this state in the tool tip. The certification
trust level is excluded for any change.
Imported primary keys also have unknown trust level, when they have
been generated in other keyrings.
Later, we should decide whether to exclude any primary key with ultimate
trust level from any further change.
It may be of interest to copy WTreeTableNode items text content. These
cannot be selected with the mouse for copy to clipboard. The text is
here shown read-only in an extended auto-replaced WLineEdit.
In-place editing with a popup if user is allowed in app config file.
User must of course manage at least a private key. User identities of
target key may be selectively chosen. Optionally, certification may be
exportable and non-revocable.
