Replace godoc.org links with pgk.go.dev (#93)

godoc.org will be discontinued and currently redirects to pkg.go.dev.

Author: TheHippo

README.md

@@ -79,7 +79,7 @@ to geography are not part of the core library (e.g. easting/northing
 conversions, ellipsoid approximations, geodetic vs. geocentric coordinates,
 etc).
 
-See http://godoc.org/github.com/golang/geo for specific package documentation.
+See https://pkg.go.dev/github.com/golang/geo for specific package documentation.
 
 For an analogous library in C++, see https://github.com/google/s2geometry, in
 Java, see https://github.com/google/s2-geometry-library-java, and Python, see
@@ -98,36 +98,36 @@ Legend:
 *   🟡 - Mostly Complete
 *   ❌ - Not available
 
-## [ℝ¹](https://godoc.org/github.com/golang/geo/r1) - One-dimensional Cartesian coordinates
+## [ℝ¹](https://pkg.go.dev/github.com/golang/geo/r1) - One-dimensional Cartesian coordinates
 
 C++ Type   | Go
 :--------- | ---
 R1Interval | ✅
 
-## [ℝ²](https://godoc.org/github.com/golang/geo/r2) - Two-dimensional Cartesian coordinates
+## [ℝ²](https://pkg.go.dev/github.com/golang/geo/r2) - Two-dimensional Cartesian coordinates
 
 C++ Type | Go
 :------- | ---
 R2Point  | ✅
 R2Rect   | ✅
 
-## [ℝ³](https://godoc.org/github.com/golang/geo/r3) - Three-dimensional Cartesian coordinates
+## [ℝ³](https://pkg.go.dev/github.com/golang/geo/r3) - Three-dimensional Cartesian coordinates
 
 C++ Type      | Go
 :------------ | ---
 R3Vector      | ✅
 R3ExactVector | ✅
 Matrix3x3     | ✅
 
-## [S¹](https://godoc.org/github.com/golang/geo/s1) - Circular Geometry
+## [S¹](https://pkg.go.dev/github.com/golang/geo/s1) - Circular Geometry
 
 C++ Type     | Go
 :----------- | ---
 S1Angle      | ✅
 S1ChordAngle | ✅
 S1Interval   | ✅
 
-## [S²](https://godoc.org/github.com/golang/geo/s2) - Spherical Geometry
+## [S²](https://pkg.go.dev/github.com/golang/geo/s2) - Spherical Geometry
 
 ### Basic Types