Auto merge of #108 - absoludity:scalar-mul-issue-91, r=pcwalton
Auto merge of #108 - absoludity:scalar-mul-issue-91, r=pcwalton

Add support for min and max methods on points (Issue #91)

Added support for min and max methods for PointND<T: num_lib::traits::Float>
Added tests for scalar multiplication of points, expecting them to fail - but they didn't.
Modularised tests so that we can have a test_min for each type, rather than test_min_nd etc.

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servo/rust-geom