* Global

- Change the format of aggregated requests
   owl_request & owl_request_info must be updated to allow
   transmission of (auto)calibration requests from the aggregator to
   the positioning server.
- Use string for network exchanges?
- Mark arguments as const in function headers if needed
   That is done in the owlps-positioning C++ code, but not constantly
   in C modules.
- Allow to use hostnames instead of IP addresses.
- Use struct ether_addr to store MAC addresses?
   We could use the struct ether_addr to store binary MAC addresses,
   and convert them to strings with ether_ntoa() instead of
   owl_mac_bytes_to_string(). See ether_aton(3).


* libowlps

- Delete timestamp_is_null()?
   This function is currently not used.


* Aggregator

- inet_ntoa() is not secure with threads
   Use inet_ntop() instead?
- Use locks to read/write the AP list
   Currently, several threads can access the list simultaneously, and
   that's not cool!
- Refactor got_request().
- Use the type of a request to identify it?
   (along with the mobile MAC address and the request time)
- got_request(): option for the maximal difference time
   For implicit packet, we consider that packet from the same MAC and
   received within an interval of 10ms are part of the same
   request. We should define an option to allow user to choose the
   time he wants.
- Allow blank parameters for output options.
- Fix segfault on SIGINT.


* Listener

- read_packet(): use ieee80211_header_size for all implicit packets
   Currently the size is corrected only for data packets.
- Fix segfault when rtap_iface is not in monitor mode (?) on Foneras.
- Merge Makefile and Makefile_atheros?
   Use autohell?
- Use positive (USE_CONFUSE) and negative (NO_USE_PTHREAD) options?
   The default options could be modified, but that's not so important,
   is it?


* Client

- Allow to use a string for the direction
   Could be nice, but probably useless.


* Positioning

- Has its own fat TODO file, which I should translate.


* writeInDb

- Do something about that
   ° Merge in owlps-positioning?
   ° Delete?