Add ROA table support
- Add bird_roa_table to application config structure.
- Add "bird_roa_table" (-t) CLI parser argument.
- Add optional addition of " table <bird_roa_table>" clause to the "add roa" command.
  - This made impossible to use a static buffer for the BIRD command.
  - Initialize bird_add_roa_table (either empty or " table <bird_roa_table>") dynamically.
  - Initialize bird_command buffer dynamically using bird_add_roa_table buffer size.
  - Added static bird_response since the dynamic bird_command buffer could be too small for the BIRD responses.