Added %d as an extended replacement for directory name

lib/block.js

@@ -28,13 +28,16 @@ Block.prototype.build = function () {
     if (this.uniqueExts) {
         var extname = path.extname(this.file.path);
         var basename = path.basename(this.file.path, extname);
-
+        var dirname = path.dirname(this.file.path);
         if (this.uniqueExts['%f']) {
             this.uniqueExts['%f'].value = basename;
         }
         if (this.uniqueExts['%e']) {
             this.uniqueExts['%e'].value = extname;
         }
+        if (this.uniqueExts['%d']) {
+            this.uniqueExts['%d'].value = dirname.split(path.sep).pop();
+        }
 
         Object.keys(this.uniqueExts).forEach(function (key) {
             var unique = this.uniqueExts[key];

lib/common.js

@@ -56,7 +56,7 @@ module.exports = {
     parseTasks: function (options) {
         options = options || {};
 
-        var utilExtensions = /%f|%e/g;
+        var utilExtensions = /%f|%e|%d/g;
         var tasksByNames = {};
 
         var tasksPromises = Object.keys(options).map(function (name) {

readme.md

@@ -98,6 +98,7 @@ Valid extended replacements are:
 
 * **%f** - this will be replaced with the filename, without an extension.
 * **%e** - this will be replaced with the extension including the `.` character.
+* **%d** - this will be replaced with the directory name.
 
 ###### Stream replacements:
 Everywhere a string replacement can be given, a stream of vinyl is also accepted. The content of each file will be treated as UTF-8 text and used for replacement. If the stream produces more than a file the behavior is the same as when an array is given.