Fixes zero width or height image reading#764

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flippmoke merged 8 commits intomasterfrom

Jun 13, 2017

Commits on May 2, 2017

Updated the version of mapnik-vector-tile for a fix associated with attempting to read an area of zero width or height from an image in a vector tile resulting in an exception. Added a new test cas…
flippmoke
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Commits on Jun 6, 2017

Merge branch 'master' into image_fix
flippmoke
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