0.9.1

Added

• futhark cuda: a new CUDA backend by Jakob Stokholm Bertelsen.

• New command for comparing data files: futhark datacmp.

• An :mtype command for futhark repl that shows the type of a
  module expression.

• futhark run takes a -w option for disabling warnings.

Changed

• Major command reorganisation: all Futhark programs have been
  combined into a single all-powerful futhark program. Instead of
  e.g. futhark-foo, use futhark foo. Wrappers will be kept
  around under the old names for a little while. futharki has
  been split into two commands: futhark repl and futhark run.
  Also, py has become python and cs has become csharp, but
  pyopencl and csopencl have remained as they were.

• The result of a function is now forbidden from aliasing a global
  variable. Surprisingly little code is affected by this.

• A global definition may not be ascribed a unique type. This never
  had any effect in the first place, but now the compiler will
  explicitly complain.

• Source spans are now printed in a slightly different format, with
  ending the line number omitted when it is the same as the start
  line number.

Fixed

• futharki now reports source locations of trace expressions
  properly.

• The type checker now properly complains if you try to define a
  type abbreviation that has unused size parameters.