v2 (#2)

* Geohash is a data struct now
* Consolidate GeohashBox into Geohash
* Add MapKit/CoreLocation helpers to Geohash
* Update README.md
* Create LICENSE

LICENSE

@@ -0,0 +1,21 @@
+MIT License
+
+Copyright (c) 2020 Alan Chu
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.

README.md

@@ -1,34 +1,77 @@
 # GeohashKit
 ![Swift](https://github.com/ualch9/GeohashKit/workflows/Swift/badge.svg)
 
-GeohashKit is a native Swift implementation of the geohash hashing algorithem. Supporting encode, decode and neighbor search. This is an indirect fork of [maximveksler/Geohashkit](https://github.com/maximveksler/GeohashKit), meant for Swift Package Manager support.
+GeohashKit is a native Swift implementation of the [Geohash hashing algorithm](https://www.movable-type.co.uk/scripts/geohash.html). Supporting encode, decode and neighbor search. 
+
+The original Swift (v1) implementation is from [maximveksler/GeohashKit](https://github.com/maximveksler/GeohashKit). The v2 implementation uses a data structure to define the Geohash as a rectangular cell, rather than just a string.
 
 ## Platforms
 - iOS, macOS, watchOS, tvOS
 - Ubuntu
 
-## API
+## API (v2)
+A `Geohash` is a data structure, representing a geohash as a rectangular cell.
 
-### Encode
+#### Initialize with coordinates ("Encode")
 ```swift
-Geohash.encode(latitude: 42.6, longitude: -5.6) // "ezs42"
+let geohash = Geohash(coordinates: (42.6, -5.6), precision: 5)
+print(geohash.geohash)      // "ezs42"
 ```
 
-###### Specify desired precision
+#### Initialize with existing geohash ("Decode")
 ```swift
-Geohash.encode(latitude: -25.382708, longitude: -49.265506, 12) // "6gkzwgjzn820"
+let geohash = Geohash(geohash: "ezs42")
+print(geohash.coordinates)  // (latitude: 42.60498046875, longitude: -5.60302734375)
 ```
 
-### Decode
+#### Neighbors
 ```swift
-Geohash.decode("ezs42")! // (latitude: 42.60498046875, longitude: -5.60302734375)
+let neighbors = Geohash(geohash: "u000").neighbors  // Returns an array of neighbor geohash cells.
+print(neighbors.north)                              // Get the north (top) cell.
+print(geohash.neighbors.all.map { $0.geohash })     // ["u001", "u003", "u002", "spbr", "spbp", "ezzz", "gbpb", "gbpc"]
 ```
 
-### Neighbor Search
+#### MapKit
 ```swift
-Geohash.neighbors("u000")! // ["u001", "u003", "u002", "spbr", "spbp", "ezzz", "gbpb", "gbpc"]
+let geohash = Geohash(geohash: "ezs42")
+let region: MKCoordinateRegion = geohash.region
 ```
 
+#### Re: Precision
+I purposely left out a precision enum. I found that explaining the approximate size of the cell at 
+a given precision was confusing, it is difficult to explain a size without using numbers (`case 2500km` is not valid Swift). 
+Geohashes are rectangular Mercator cells with true size dependent on the latitude, so 
+defining a `case twentyFiveHundredKilometers` is still not necessarily true.
+
+<details>
+  <summary>v1 API (maximveksler/GeohashKit compatible)</summary>
+  To use the maximveksler-compatible API, checkout exactly  `1.0`:
+
+  ```swift
+  .package(url: "https://github.com/ualch9/geohashkit.git", .exact("1.0"))
+  ```
+
+  ### Encode
+  ```swift
+  Geohash.encode(latitude: 42.6, longitude: -5.6) // "ezs42"
+  ```
+
+  ### Specify desired precision
+  ```swift
+  Geohash.encode(latitude: -25.382708, longitude: -49.265506, 12) // "6gkzwgjzn820"
+  ```
+
+  ### Decode
+  ```swift
+  Geohash.decode("ezs42")! // (latitude: 42.60498046875, longitude: -5.60302734375)
+  ```
+
+  ### Neighbor Search
+  ```swift
+  Geohash.neighbors("u000")! // ["u001", "u003", "u002", "spbr", "spbp", "ezzz", "gbpb", "gbpc"]
+  ```
+</details>
+
 ## Install
 Use Swift Package Manager.