Mark std.stdio.LockingTextWriter.this, ~this and this(this) as @trusted
Merge pull request #2217 from tom-tan/trusted-stdio-LockingTextWriter-ctor-dtor-postblt

Mark std.stdio.LockingTextWriter.this, ~this and this(this) as @trusted
Merge pull request #2222 from jmdavis/datetime

Remove workarounds for some compiler bugs which were fixed
More ref return fixes in std.datetime now that the compiler allows them.
Fix deprecation warnings in std.datetime.