Move peerNumberIsOurs.
Add ToxFileSender.
Change signature of FileSendData.

Now it is only SendData in the ToxFileSender object.

Furthermore accepts arbirtrary ranges of arrays.
Add ToxExtensions class.
Add extension for SendData.
Add constructor overload for tox with no parameters.

Uses default parameters.
Change default options for ToxOptions in Tox constructor.
Move IsConnected code to Iterate.

This ensures that the iterate functions works stand alone
just like the the Loop function.
Move GetGroupMemberName to ToxGroup
Add Groups field in Tox instance.
Move GroupPeerPublicKey to ToxGroupPeer
Adjust FileSender event args to hold ToxFileSender.
Make toxgroup instatiation internal.
Multiplex on our own between sending and receiving FileSenders.
Calculate the offset in FileSendData correctly.