Libtorrent

* add router.utorrent.com to list of DHT bootstrap nodes
* Android builds with new NDK r21d
* lt: validate UTF-8 encoding of client version strings from peers
* lt: don't time out tracker announces as eagerly while resolving hostnames
* lt: fix NAT-PMP shutdown issue
* lt: improve hostname lookup by merging identical lookups
* lt: fix network route enumeration for large routing tables
* lt: fixed issue where pop_alerts() could return old, invalid alerts
* lt: fix issue when receiving have-all message before the metadata
* lt: don't leave lingering part files handles open
* lt: disallow calling add_piece() during checking
* lt: fix incorrect filename truncation at multi-byte character
* lt: always announce listen port 1 when using a proxy

* add set_alert_fd in python binding, to supersede set_alert_notify
* fix bug in part files > 2 GiB
* add function to clear the peer list for a torrent
* fix resume data functions to save/restore more torrent flags
* limit number of concurrent HTTP announces
* fix queue position for force_rechecking a torrent that is not auto-managed
* improve rate-based choker documentation, and minor tweak
* undeprecate upnp_ignore_nonrouters (but referring to devices on our subnet)
* increase default tracker timeout
* retry failed socks5 server connections
* allow UPnP lease duration to be changed after device discovery
* fix IPv6 address change detection on Windows

* libtorrent 1.2.7 update (ce0a85f783bec37484776a37fe3662279091ecc5)
* upgraded to boost 1.73.0
* upgraded to openssl 1.1.1g
* lt: fix incorrect filename truncation at multi-byte character
* lt: always announce listen port 1 when using a proxy
* lt: add set_alert_fd in python binding, to supersede set_alert_notify
* lt: fix bug in part files > 2 GiB
* lt: add function to clear the peer list for a torrent
* lt: fix resume data functions to save/restore more torrent flags
* lt: limit number of concurrent HTTP announces
* lt: fix queue position for force_rechecking a torrent that is not auto-managed
* lt: improve rate-based choker documentation, and minor tweak
* lt: undeprecate upnp_ignore_nonrouters (but refering to devices on our subnet)
* lt: increase default tracker timeout
* lt: retry failed socks5 server connections
* lt: allow UPnP lease duration to be changed after device discovery
* lt: fix IPv6 address change detection on Windows
* lt: fix peer timeout logic
* lt: simplify proxy handling. A proxy now overrides listen_interfaces
* lt: fix issues when configured to use a non-default choking algorithm
* lt: fix issue in reading resume data
* lt: revert NXDOMAIN change from 1.2.4
* lt: don't open any listen sockets if listen_interfaces is empty or misconfigured
* lt: fix bug in auto disk cache size logic
* lt: fix issue with outgoing_interfaces setting, where bind() would be called twice
* lt: add build option to disable share-mode
* lt: support validation of HTTPS trackers
* lt: deprecate strict super seeding mode
* lt: make UPnP port-mapping lease duration configurable
* lt: deprecate the bittyrant choking algorithm
* lt: add build option to disable streaming

* fix peer timeout logic
* simplify proxy handling. A proxy now overrides listen_interfaces
* fix issues when configured to use a non-default choking algorithm
* fix issue in reading resume data
* revert NXDOMAIN change from 1.2.4
* don't open any listen sockets if listen_interfaces is empty or misconfigured
* fix bug in auto disk cache size logic
* fix issue with outgoing_interfaces setting, where bind() would be called twice
* add build option to disable share-mode
* support validation of HTTPS trackers
* deprecate strict super seeding mode
* make UPnP port-mapping lease duration configurable
* deprecate the bittyrant choking algorithm
* add build option to disable streaming

* There was no 1.2.6 release, we waited and jumped all the way to 1.2.7.0

* announce port=1 instead of port=0, when there is no listen port
* fix LSD over IPv6
* support TCP_NOTSENT_LOWAT on Linux
* fix correct interface binding of local service discovery multicast
* fix issue with knowing which interfaces to announce to trackers and DHT
* undeprecate settings_pack::dht_upload_rate_limit