Setup API for `lftpd`

* add dynamic api handlers
* move config setup logic in api call to be dynamically reconfigured

Signed-off-by: Oleg Verych <olecom@gmail.com>
config: rework it into api for easy reloading and dynamic changes

Signed-off-by: Oleg Verych <olecom@gmail.com>
api: /lib/cfg

name config specific api as 'cfg' with its own file

Signed-off-by: Oleg Verych <olecom@gmail.com>
api cfg: noop comments cleanup

Signed-off-by: Oleg Verych <olecom@gmail.com>
Merge pull request #2 from suprojs/adopt_module_provide_close_#1

Adopt module provide API close #1