libsoup-2.4.sym: remove nonexistent symbol

It was added accidentally at 1c71cb223b00eaa5c776229d9e0312ba852ef87a

https://bugzilla.gnome.org/show_bug.cgi?id=738003
libsoup: add a "make check" rule to verify libsoup-2.4.sym

Add a "make check" rule to verify libsoup-2.4.sym (which requires
fixing some incorrect sorting as well).
libsoup: only do the libsoup-2.4.sym check on linux
Updated Bengali (India) translation
Updated Latvian translation
Added missing symbol soup_server_get_uris() to the documentation.
libsoup-2.4.sym: Added missing symbol

Added missing symbol soup_server_set_ssl_cert_file()
soup_message_get_https_status(): Improved documentation

Added a note that this API is only meaningful in the context
of a SoupSession (i.e. it's not meaningful for a SoupServer).
Updated Ukrainian translation
Fix build on Windows

Avoid the use of 'interface' variable name in public headers to avoid
conflicting with the "#define interface struct" that Windows headers do.

https://bugzilla.gnome.org/show_bug.cgi?id=738551
soup-session: clarify default session features

Document what features exist on a SoupSession by default.

Suggested by Michael Catanzaro.
https://bugzilla.gnome.org/show_bug.cgi?id=737689
soup-message-io: do an async close when doing non-blocking I/O

When using chunked encoding, SoupBodyOutputStream needs to write the
final "0" chunk when it's closed, and thus may block. So we have to do
an async close in the non-blocking case.

(This also requires changing continue-test to not trace "finished"
events, since it becomes unpredicatable exactly when they'll happen
now.)

https://bugzilla.gnome.org/show_bug.cgi?id=727138
Add missing (nullable) annotations, assorted minor introspection fixes

https://bugzilla.gnome.org/show_bug.cgi?id=729987
introspection: Fix some g-ir-scanner warnings

https://bugzilla.gnome.org/show_bug.cgi?id=729987
Add missing array annotations for binary data

https://bugzilla.gnome.org/show_bug.cgi?id=729987
SoupConnection: fix connection in TLS_HANDSHAKING event signal

SoupConnection was generating its own :event signals for
TLS_HANDSHAKING/TLS_HANDSHAKED, since we don't use GSocketClient's TLS
negotiation, and so just re-emitting the socket client signal won't
cover that.

However, it ended up emitting it before the SoupSocket had even
created the GTlsClientConnection, and so was emitting it with the
GTcpConnection, contrary to the documentation.

Fix this by making the SoupSocket generate those event signals at the
correct time, and having SoupConnection just re-emit them. Also, add
code to connection-test to verify that each even is emitted with the
expected kind of GIOStream.

https://bugzilla.gnome.org/show_bug.cgi?id=739951
2.49.1
Updated Turkish translation
cache: Do not add Age header to all responses

I think we were doing this because RFC 2616 says:

"When a response is generated from a cache entry, the cache MUST include a single Age
header field in the response with a value equal to the cache entry's current_age."

But it also says:

"The presence of an Age header field in a response implies that a
response is not first-hand. However, the converse is not true, since
the lack of an Age header field in a response does not imply that the
response is first-hand unless all caches along the request path are
compliant with HTTP/1.1"

We are always adding the Age header, even for responses sent after a
revalidation, in which case the response is first-hand. So at least
after a revalidation we should not include the Age header. However,
other browsers don't seem to include the Age header in any case, and the
first quote from RFC 2616 is not present in RFC 7234. So, the safest
approach that is compatible with other browsers and RFC compliant is to
never include the Age header manually in cache responses.

This avoids unnecessary conditional requests made when a resource is
considered expired because of the Age header added after a revalidation.

https://bugzilla.gnome.org/show_bug.cgi?id=741108
soup-version.h: add 2.50 macros