Ensure fp.mergeAllWith accepts more than 2 sources. [closes #2786]

fp/_mapping.js

@@ -172,9 +172,9 @@ exports.iterateeRearg = {
 
 /** Used to map method names to rearg configs. */
 exports.methodRearg = {
-  'assignInAllWith': [1, 2, 0],
+  'assignInAllWith': [1, 0],
   'assignInWith': [1, 2, 0],
-  'assignAllWith': [1, 2, 0],
+  'assignAllWith': [1, 0],
   'assignWith': [1, 2, 0],
   'differenceBy': [1, 2, 0],
   'differenceWith': [1, 2, 0],
@@ -183,7 +183,7 @@ exports.methodRearg = {
   'intersectionWith': [1, 2, 0],
   'isEqualWith': [1, 2, 0],
   'isMatchWith': [2, 1, 0],
-  'mergeAllWith': [1, 2, 0],
+  'mergeAllWith': [1, 0],
   'mergeWith': [1, 2, 0],
   'padChars': [2, 1, 0],
   'padCharsEnd': [2, 1, 0],
@@ -206,15 +206,15 @@ exports.methodRearg = {
 /** Used to map method names to spread configs. */
 exports.methodSpread = {
   'assignAll': { 'start': 0 },
-  'assignAllWith': { 'afterRearg': true, 'start': 1 },
+  'assignAllWith': { 'start': 0 },
   'assignInAll': { 'start': 0 },
-  'assignInAllWith': { 'afterRearg': true, 'start': 1 },
+  'assignInAllWith': { 'start': 0 },
   'defaultsAll': { 'start': 0 },
   'defaultsDeepAll': { 'start': 0 },
   'invokeArgs': { 'start': 2 },
   'invokeArgsMap': { 'start': 2 },
   'mergeAll': { 'start': 0 },
-  'mergeAllWith': { 'afterRearg': true, 'start': 1 },
+  'mergeAllWith': { 'start': 0 },
   'partial': { 'start': 1 },
   'partialRight': { 'start': 1 },
   'without': { 'start': 1 },

lodash.js

@@ -10822,6 +10822,7 @@
         if (array) {
           arrayPush(otherArgs, array);
         }
+        arrayPush(otherArgs, castSlice(args, start + 1));
         return apply(func, this, otherArgs);
       });
     }

test/test.js

@@ -20866,8 +20866,8 @@
         args = slice.call(arguments);
       });
 
-      spread([4, 2], 'ignored');
-      assert.deepEqual(args, [4, 2]);
+      spread([1, 2], 3);
+      assert.deepEqual(args, [1, 2, 3]);
     });
 
     QUnit.test('should work with `start`', function(assert) {