removed obsolete FIXMEs. formatting changes.
IPv6 struct
changed outdated match on IpAddr
converted UvUdpSocket into a newtype struct
Converted UdpSocket into a newtype struct and (dis)connecting uses move semantics rather than ~.
removed unecessary method
converted TCP interface to newtype structs
cleaned up uv/net
changed NOTE to TODO
std::rt: Some cleanup
Refactored the runtime to view coroutines as a component of tasks, instead of tasks as a component of coroutines.
rt: Add global_args_lock functions to rustrt.def.in
merging task/coroutine refactoring back into upstream
removed unnecessary import that slipped in during merge
std::rt: Ignore homed task tests
A missing ! made it so that the testcase schedule_home_states was throwing spurious assert failures. Why this did not result in the test case failing previously is beyond me.
Merge remote-tracking branch 'toddaaro/niots'

Conflicts:
	src/libstd/rt/sched.rs
std: Use the same task failure message as C++ rt
IPv6 support for UDP and TCP.
Merge remote-tracking branch 'upstream/io' into io

Conflicts:
	src/libstd/rt/test.rs
	src/rt/rustrt.def.in