Update the documentation.
We can't return public id on `ndpi_guess_host_protocol_id()` because we
use that value internally:
```
src/lib/ndpi_main.c: flow->guessed_protocol_id_by_ip = ndpi_guess_host_protocol_id(ndpi_str, flow);
```
It was completly broken.
Pay some attention to HTTP case where we might have Host header in the
"$DOMAIN:$PORT" form: we usually want to strip the port part
`memrchr` is not available on macOS and on Windows: create a wrapper
Right now, there is, in essence, a static mapping between flow protocols
and flow breeds.
Make it dynamic: allow to have different flows, with the same
classification but differents breeds. This is the same logic that we
already have for categories....
Preliminary work to support breed in category lists.
API change from the app POV: to get the flow breed don't use anymore
`ndpi_get_proto_breed()`, but access directly `struct ndpi_proto->breed`
The functions `ndpi_domain_classify_*()` and
`ndpi_get_host_domain_suffix()` now have a `u_int32_t` parameter as
`class_id` (instead of `u_int_16_t`), with the following logic:
```
class_id = (breed << 16) | category
```
instead of the old:
```
class_id = category
```
Please note that this change is back-compatible: if you are not
interested into breeds, you don't need to update the application code.
```
ndpi_analyze.c: In function ‘ndpi_deserialize_ranking’:
ndpi_analyze.c:2244:3: warning: ignoring return value of ‘fread’ declared with attribute ‘warn_unused_result’ [-Wunused-result]
2244 | fread(&rank->header, sizeof(ndpi_ranking_header), 1, fd);
| ^~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
ndpi_main.c: In function ‘ndpi_match_host_subprotocol’:
ndpi_main.c:11798:9: warning: ‘__builtin_strncpy’ output may be truncated copying between 0 and 63 bytes from a string of length 255 [-Wstringop-truncation]
11798 | strncpy(str, string_to_match, ndpi_min(string_to_match_len, sizeof(str)-1));
| ^
ndpi_main.c:11811:7: warning: ‘__builtin_strncpy’ output may be truncated copying between 0 and 63 bytes from a string of length 255 [-Wstringop-truncation]
11811 | strncpy(str, string_to_match, ndpi_min(string_to_match_len, sizeof(str)-1));
```
