Tweaked gitignore

gitignore removed all composer and npm files, so automated builds would fail

conf/site/node_modules/collect.js/docs/api/diffKeys.md

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+# `diffKeys()`
+
+The diffKeys method compares the collection against another collection or a plain object based on its keys. This method will return the key / value pairs in the original collection that are not present in the given collection:
+
+```js
+const collection = collect({
+  a: 'a',
+  b: 'b',
+  c: 'c',
+  d: 'd',
+});
+
+const diff = collection.diffKeys({
+  b: 'b',
+  d: 'd',
+});
+
+diff.all();
+
+// { a: 'a', c: 'c' }
+```
+
+[View source on GitHub](https://github.com/ecrmnn/collect.js/blob/master/src/methods/diffKeys.js)