Revert "Fix #3691"

This reverts commit 500d615f69899c1601af7e0e512754f957a9ef39.

Conflicts:
	base/task.jl
fix #3691 better
restore some libuv.state arbitrarily lost in bdb61666d106ffb859d1d672c7b4c79308601c00
moved repr from io.jl to string.jl
as it is used in pcre.jl
probably fix #3686
fix #3406
help #3680 by at least printing the error message before crashing
allow trailing 1s in subarray indexing. fixes #3697
fix typo in DL_LOAD_PATH usage in dlload
fix #3698
don't silently swallow getaddrinfo failures
Add back accidentally reverted getaddrinfo error checking
Fix typo in connect
Fix small typo
addprocs_{scyld,sge}: if it errors, it's discontinued, not deprecated.
sorting: allow composition of `by` and `lt` keywords.

Reorder the arguments to `ord` -- this is strictly internal; I was
considering removing the `order` keyword altogether but a) it could
be useful to someone and b) not having the `order` keyword would
make deprecating the old interface a nightmare.
abort send_del_client for removed workers.
this allows the RemoteRef finalizer to return without an error for
removed workers, which is what we want. then we can print errors from
finalizers without getting unwanted messages in this case.
Add FAQ section on abstract fields of types
Pkg2: only fast-forward when auto-pulling repos, don't fail.
Add an additional illustration of function specialization