Merge pull request #5 from magento-commerce/imported-magento-magento-coding-standard-199

[Imported] Master update

Author: sivaschenko

Magento2/Sniffs/Functions/DiscouragedFunctionSniff.md

@@ -0,0 +1,11 @@
+# Rule: getimagesize() is discouraged
+
+## Reason
+
+[getimagesize](https://www.php.net/manual/en/function.getimagesize.php) function works only with local and supported streams. 
+With introduction of more advanced storages, like AWS S3 or Azure Blob Storage this function will cause issues where file is not accessible.
+
+## How to fix
+
+[getimagesizefromstring](https://www.php.net/manual/en/function.getimagesizefromstring.php) can be used instead to retrieve all the information from file.
+This function works with data strings, so you should read the file content using specific adapter before using it.