--remove description of CONFIG_PTP_*
--add description of CONFIG_PTP_PORT_PARAMS and CONFIG_PTP_CUSTOM
--update description of CONFIG_PORTxx_PARAMS, add proto information
--update timing configuration section with proto and role information
--In apply_dot-config description add hyperlink to chapter where dot-config is
  described instead of document itself. It looks like this part was copied from
  developer-manual.
--by changes above remove information that role is not used.

Signed-off-by: Adam Wujek <adam.wujek@cern.ch>