Fixes for geom

[gdey]

fixes for geom needed for constraints

[coveralls]

Pull Request Test Coverage Report for Build 275

• 13 of 29 (44.83%) changed or added relevant lines in 3 files are covered.
• 1 unchanged line in 1 file lost coverage.
• Overall coverage increased (+0.1%) to 57.338%

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Changes Missing Coverage	Covered Lines	Changed/Added Lines	%
planar/triangulate/gdey/quadedge/subdivision/subdivision.go	0	2	0.0%
encoding/mvt/feature.go	0	14	0.0%

Files with Coverage Reduction	New Missed Lines	%
encoding/mvt/feature.go	1	38.42%

Totals
Change from base Build 269:	0.1%
Covered Lines:	5446
Relevant Lines:	9498

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💛 - Coveralls

[gdey]

Travis CGO_ENABLED=0 is failing because it is unable to get github.com/mattn/go-sqlite3 as a dependency. I don't know of a way to prevent it from getting this dependency. Which is only needed when cgo is enabled.