Make paragraph metrics configurable externally.

Author: SergioEstevao

Aztec/Classes/Constants/Metrics.swift

@@ -4,12 +4,12 @@ import Foundation
 /// A collection of constants and metrics shared between the Aztec importer
 /// and the editor.
 ///
-enum Metrics {
+public enum Metrics {
 
-    static let defaultIndentation = CGFloat(12)
-    static let maxIndentation = CGFloat(200)    
-    static let listTextIndentation = CGFloat(16)
-    static let tabStepInterval = 8
-    static let tabStepCount = 12
-    static let paragraphSpacing = CGFloat(6)
+    public static var defaultIndentation = CGFloat(12)
+    public static var maxIndentation = CGFloat(200)
+    public static var listTextIndentation = CGFloat(16)
+    public static var tabStepInterval = 8
+    public static var tabStepCount = 12
+    public static var paragraphSpacing = CGFloat(6)
 }