agent: Put Token lines into the key files.
* agent/findkey.c (write_extended_private_key): Add args serialno and keyref. Write a Token line if that does not yet exist. (agent_write_private_key): Add args serialno and keyref and change all callers. (agent_write_shadow_key): Skip leading spaces. * agent/keyformat.txt: Improve extended key format docs.
Noet that the extended key forma is the defaqult in 2.3. This patch
is a first step to better handle tokens which carray the same key.
- Signed-off-by: Werner Koch <wk@gnupg.org>