Make constructors of std.file.FileException @safe or @trusted
Mark a constructor for version(Windows) as @trusted
Remove conflict template function

By fixing bug 10811, both toUTFz template functions will conflict on the call `toUTFz!(T)(str)`. Remove one to resolve ambiguity.
Merge pull request #1473 from 9rnsr/fix10811

Supplemental fix for issue 10811 - Remove conflict template function
Mark a constructor for Windows as @safe
Make std.file.deleteme @safe
Merge pull request #1449 from tom-tan/safe-file-FileException

Make constructors of std.file.FileException @safe and @trusted
Merge pull request #1474 from tom-tan/safe-file-deleteme

Make std.file.deleteme @safe