Fixed documentation comment errors
Fix win32 mingw native build

toxdns was not linking because of references to functions in crypto_core
Merge branch 'jin-eld-fix-code-doc'
Merge branch 'fix-mingw32-native' of https://github.com/jin-eld/ProjectTox-Core
Attempted fix of file transfer issue.

Instead of dropping the rate to minimum just half it until it drops
to the minimum.
Packets can now be sent from the connection status callback.
Set packets_left to default non zero values when creating connection.
Change connection status before handling data packets.
Fixed file sending documentation.
Fixed bug with TCP.

Don't increment nonce if packet was discarded instead of being sent.
Fixed TCP bug.

Packet was being copied with a wrong, smaller length.
added priority packet system for TCP server
fixed some issues
Merge branch 'notsecure-split-video'
applied priority queue changes to the TCP client too
fix memory leak
Merge branch 'JFreegman-memleak'
Merge branch 'split-video' of https://github.com/notsecure/toxcore
Fixed possible bug with TCP nonce not getting incremented.
Build system now automatically enables epoll support in TCP server
when supported.