archivers/ruby-xz: update to 1.0.0

== 1.0.0 (2018-05-20)

* *BreakingChange* The XZ module's methods now take any parameters
  beyond the IO object as real Ruby keyword arguments rather than
  a long argument list.
* *BreakingChange* XZ.decompress_stream now honours Ruby's
  external and internal encoding concept instead of just
  returning BINARY-tagged strings.
* *BreakingChange* Remove deprecated API on stream reader/writer
  class and instead sync the API with Ruby's zlib library
  (Ticket #12 by me).
* *BreakingChange* StreamWriter.new and StreamReader.new do not accept
  a block anymore. This is part of syncing with Ruby's zlib API.
* *BreakingChange* StreamReader.open and StreamWriter.open always
  return the new instance, even if a block is given to the method
  (previous behaviour was to return the return value of the block).
  This is part of the syncing with Ruby's zlib API.
* *BreakingChange* StreamReader.new and StreamWriter.new as well as
  the ::open variants take additional arguments as real Ruby keyword
  arguments now instead of a long parameter list plus options hash.
  This is different from Ruby's own zlib API as that one takes both
  a long parameter list and a hash of additional options. ruby-xz
  is meant to follow zlib's semantics mostly, but not as a drop-in
  replacement, so this divergence from zlib's API is okay (also
  given that it isn't possible to replicate all possible options
  1:1 anyway, since liblzma simply accepts different options as
  libz). If you've never used these methods' optional arguments,
  you should be fine.
* *BreakingChange* Stream#close now returns nil instead of the
  number of bytes written. This syncs Stream#close with Ruby's
  own IO#close, which also returns nil.
* *BreakingChange* Remove Stream#pos=, Stream#seek, Stream#stat. These
  methods irritated the minitar gem, which doesn't expect them to
  raise NotImplementedError, but directly to be missing if the object
  does not support seeking.
* *BreakingChange* StreamReader and StreamWriter now honour Ruby's
  encoding system instead of returning only BINARY-tagged strings.
* *Dependency* Remove dependency on ffi. ruby-xz now uses fiddle from
  the stdlib instead.
* *Dependency* Remove dependency on io-like. ruby-xz now implements
  all the IO mechanics itself. (Ticket #10 by me)
* *Dependency* Bump required Ruby version to 2.3.0.
* *Fix* libzlma.dylib not being found on OS X (Ticket #15 by
  s0nspark).

(taca)