v0.6.1: start off with all workers on the node as affinity to FileRef (#89)

* start off with empty affinity for FileRefs

* bump MemPool requirement

* FileRef default affinity should be all workers on the host where the file resides

* update test

v0.6.0: Merge pull request #86 from JuliaParallel/s/less-types

Reduce over-specialization

v0.5.3: Merge pull request #80 from JuliaParallel/tan/scheduler

fix darray chunk refcount to survive serialization

v0.5.2

refcounting

v0.5.1

remove debug statement

v0.5.0: Merge pull request #67 from JuliaParallel/s/sort2

Batched sort algorithm

v0.4.0

__precompile__

use MemPool

v0.3.2

Merge remote-tracking branch 'origin/master'

v0.3.1

update build matrix

v0.3.0

add 0.6 to build matrix, make 0.6 only