Add public initializers to KeyPath

Himotoki.podspec

@@ -1,6 +1,6 @@
 Pod::Spec.new do |s|
   s.name         = "Himotoki"
-  s.version      = "0.4"
+  s.version      = "0.4.1"
   s.summary      = "A type-safe JSON decoding library purely written in Swift"
   s.description  = <<-DESC
 Himotoki (紐解き) is a type-safe JSON decoding library purely written in Swift. This library is highly inspired by popular JSON parsing libraries in Swift: [Argo](https://github.com/thoughtbot/Argo) and [ObjectMapper](https://github.com/Hearst-DD/ObjectMapper).

Himotoki/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>FMWK</string>
 	<key>CFBundleShortVersionString</key>
-	<string>0.4</string>
+	<string>0.4.1</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>

Himotoki/KeyPath.swift

@@ -8,29 +8,37 @@
 
 public struct KeyPath {
     public let components: [String]
+
+    public init(_ key: String) {
+        self.init([key])
+    }
+
+    public init(_ components: [String]) {
+        self.components = components
+    }
 }
 
 extension KeyPath: StringLiteralConvertible {
     public typealias UnicodeScalarLiteralType = StringLiteralType
     public typealias ExtendedGraphemeClusterLiteralType = StringLiteralType
 
     public init(unicodeScalarLiteral value: UnicodeScalarLiteralType) {
-        components = [value]
+        self.init(value)
     }
 
     public init(extendedGraphemeClusterLiteral value: ExtendedGraphemeClusterLiteralType) {
-        components = [value]
+        self.init(value)
     }
 
     public init(stringLiteral value: StringLiteralType) {
-        components = [value]
+        self.init(value)
     }
 }
 
 extension KeyPath: ArrayLiteralConvertible {
     public typealias Element = String
 
     public init(arrayLiteral elements: String...) {
-        components = elements
+        self.init(elements)
     }
 }

HimotokiTests/Info.plist

@@ -15,7 +15,7 @@
 	<key>CFBundlePackageType</key>
 	<string>BNDL</string>
 	<key>CFBundleShortVersionString</key>
-	<string>0.4</string>
+	<string>0.4.1</string>
 	<key>CFBundleSignature</key>
 	<string>????</string>
 	<key>CFBundleVersion</key>