libbnetapi: BUrlRequest now outputs to BDataIO

Previously, BUrlRequest returns data received via a callback that can't
return any value. This approach have several issues:

- It's not possible to signify failures to the request.
- Users have to implement custom listeners just to handle the common
case of outputting to a buffer/file/etc.
- The received data has to be serialized into BMessage when
BUrlProtocolDispatchingListener is employed. This can cause a
noticible slowdown in real-world scenarios as evident by #10748.

With this change, BUrlRequest will output directly into a BDataIO, which
exposes a richer API for request handlers to work with (for example a
BitTorrent client can request a BPositionIO for non-linear data
delivery), as well as simplifying common cases for users.

The adaptation only requires one additional API:
BHttpRequest::SetStopOnError(). This API simply instructs the HTTP
request handler to cancel the request if an HTTP error is occurred.

Change-Id: I4160884d77bff0e7678e0a623e2587987704443a
Reviewed-on: https://review.haiku-os.org/c/haiku/+/3084
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

libpackage.so: change UrlProtocolListener size types to off_t

Missed this use after changing the definition in hrev54926

Change-Id: I046560ec73dfb3ed6284513a34228b8343c5cf40

Package Kit: switch to libnetservices.a

Switch to the experimental services API as the copy in libbnetapi.so is
deprecated.

Change-Id: Ia0742038937d078c6a59ae13180a00a4c4eeb177
Reviewed-on: https://review.haiku-os.org/c/haiku/+/3671
Reviewed-by: Adrien Destugues <pulkomandy@gmail.com>

Package Kit: Return proper errors in FetchFileJob

This should give more meaningful errors in pkgman
(not so sure, feel free to tweak the mapping),
and also avoid running the next job if fetching failed.

Change-Id: If76968f705ff25f7ecf1a5f91d88a02040d24665
Reviewed-on: https://review.haiku-os.org/c/haiku/+/2186
Reviewed-by: Ryan Leavengood <leavengood@gmail.com>

Remove Curl, Switch to NetApi in Package Kit

Change-Id: I92213ab60dc987175c323d1d9ed11ac8b3517f2f
Reviewed-on: https://review.haiku-os.org/475
Reviewed-by: waddlesplash <waddlesplash@gmail.com>