Updated docs to reflect that the flattenDirectories was deprecated in…

… favor of 'flatten'. Also added an error message about it. See balderdashy/sails@024991f#commitcomment-18785447 for context.

README.md

@@ -293,8 +293,8 @@ require('include-all').aggregate({
 | filter      | only include modules whose FILENAME matches this regex. default `undefined`
 | pathFilter  | only include modules whose FULL RELATIVE PATH matches this regex (relative from the entry point directory). default `undefined`
 | dontLoad    | if `dontLoad` is set to true, don't run the module w/ V8 or load it into memory-- instead, return a tree representing the directory structure (all extant file leaves are included as keys, with their value = `true`)
-| flattenDirectories | if enabled, ALL modules appear as top-level keys in the dictionary-- even those from within nested directories.
-| keepDirectoryPath | Only relevant if `flattenDictionaries` is `true`.  If enabled, this option causes include-all to include the directory path in the key names.
+| flatten     | if enabled, ALL modules appear as top-level keys in the dictionary-- even those from within nested directories.
+| keepDirectoryPath | Only relevant if `flatten` is `true`.  If enabled, this option causes include-all to include the relative paths in the key names (for nested modules from subdirectories path in the key names).
 
 
 ## High-Level Options

lib/help-include-all-sync.js

@@ -48,10 +48,10 @@ var _ = require('lodash');
  *
  * @optional {Boolean} keepDirectoryPath
  *           See README
- *           Note that flattenDirectories must also be set to `true` for this to work.
+ *           Note that `flatten` must also be set to `true` for this to work.
  *           @default false
  *
- * @optional {Boolean} flattenDirectories
+ * @optional {Boolean} flatten
  *           See README
  *           @default false
  *
@@ -109,7 +109,7 @@ var _ = require('lodash');
 module.exports = function includeAll(options) {
   options = options || {};
 
-  // Assertions
+  // Assertions about usage
   if (typeof options.dirname === 'undefined') {
     throw new Error('`dirname` is required');
   }
@@ -122,6 +122,10 @@ module.exports = function includeAll(options) {
   if (typeof options.exclude !== 'undefined' && (typeof options.exclude !== 'object' || options.exclude === null)) {
     throw new Error('If specified, `exclude` must be an array of RegExps.');
   }
+  // Deprecations:
+  if (typeof options.flattenDirectories !== 'undefined') {
+    throw new Error('As of include-all v1.0.1, `flattenDirectories` was replaced with `flatten`.  See https://github.com/balderdashy/include-all#options for more information.');
+  }
 
 
   // Sane defaults: