Major bump to use latest GHC and version 3.8.2 of ArrayFire.

  - Adds stack.yaml
  - 3.8.2 bump fixes variance and product calculations in arrayfire-haskell tests
  - Tests on latest GHC versions

Bump version to 0.6.0.0.

Bump 0.5.1.0

Bump 0.5.0.0

Bump to 0.4.0.0

Bump to 0.3.0.0.

Bump to 0.2.0.0 (#18)

Enforce Complex on 'imag' and 'real' functions. (#16)

* Enfore Complex on 'imag' and 'real' functions.

* Constrain real/imag on RealFrac.