Add the ReductionBlazeFunc object, 'any', 'all', 'sum', 'product'
Update execution engine to be able to execute the reduction kernels
Add 'min' and 'max' reduction ufuncs
Add a test for reductions based on the min function
Add identity to blaze.sum, tests for it
Add sanity check tests for the rest of the reductions
Add some small computation examples to quickstart.rst
Merge pull request #195 from mwiebe/reddispatch

Add ReductionBlazeFunc and instances using it