remove no more used module use-age
pod update
params: introducing dir_users
new command: user
deporting all command implementations to their own modules

since App::Cmd is use-ing all available commands, it makes sense to
deport as much code as possible (and thus as much module loading as
possible) to lone modules that will only be require-d if needed.
Config: introducing $config var
config: allow to remove a config key
Params: introducing $params var
logging: log.level config option
log: allow to prefix a timestamp
log: allow to prefix a trace
pod & doc update
Users: introducing $users var
users: simplifying register()
die if command implementation has errors
user: possibility to delete a user
renaming W:Collection to W:Feeds to follow convention
update: log pid during operation
v0.002

    - new commands: user
    - config: possibility to delete a config (-d option)
    - log: possibility to timestamp (-t option, log.timestamp config)
    - log: possibility to trace (-T option, log.trace config)
    - update: logging pid to better follow output
    - all commands deported in their own modules to speed startup
    - W:Collection moved to W:Feeds