Qcache

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* Update dependencies on lz4 and tornado
* Allow float type hinting

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* Never released

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* Downgrade to Pandas 0.20.3 in an attempt to fix 14.

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* Numexpr filter engine is not available anymore, only Pandas. Numexpr is no longer a requirement of qcache.
NB! Major backwards incompatibility
* Fix 12, like now ignores NaN
* Fix 13, only empty string is considered as NaN when reading CSV
* Fix 8, integer standins remain integers
* Upgrade Pandas to 0.21.0 and Numpy to 0.13.1

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* Bump Pandas to 0.19.2

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* Support client cert verification