0.2.0.1 [2018.09.24]
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* Loosen STM bounds for new stackage release.
* Ditch GHC 7.6.3 support.

0.2.0 [2018.09.20]
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* Complete rework to be actually practical.
* Switched to standalone module hierarchy.
* Added functionality for parallel tasks.
* Add module which uses exceptions, instead of results to signal failure.