EqualsExact (non-spatial) method

[peterstace]

Would be useful for the Geometry interface to have an Equals method that just checks if the representation is exactly the same (similar to behaviour of reflect deep equal).

It would essentially just check that the types are exactly the same, and then iterate over all coordinates comparing them.

[peterstace]

This is pretty similar to equalsExact from geos: http://geos.refractions.net/ro/doxygen_docs/html/classgeos_1_1geom_1_1Geometry.html#a48

Maybe we just want that instead...

[peterstace]

Would also be useful to ignore ordering differences during the comparison, e.g.:

• Ignoring forwards/backwards order for LineStrings
• Ignoring ring direction in Polygons
• Ignoring order of holes in Polygons
• Ignoring order of points in multipoints

Could use the "options" pattern in Go, i.e.

type interface Geometry {
    ...
    EqualsExact(other Geometry, opts ...EqualsExactOption)
    ....
}

The options could be:

func Tolerance(tol float64) EqualsExactOption {
    ...
}

var IgnoreOrder = EqualsExactOption(...)