Issue #3341240: Replace README.txt to README.md.

README.md

+# Metatag Import Export CSV
+
+MetaTag Import Export CSV can be used to import metatags form a CSV
+file or Export metatags to a CSV file. Module supports 4 fields which
+are provided by Metatag module.
+
+For a full description of the module, visit the
+[project page](https://www.drupal.org/project/metatag_import_export_csv).
+
+Submit bug reports and feature suggestions, or track changes in the
+[issue queue](https://www.drupal.org/project/issues/metatag_import_export_csv).
+
+
+## Description
+
+- This module has two separate forms for import and export.
+    - Export - you can select the entity type(node,user,taxonomy), bundle type
+              (content type,vocabulary),tags and delimeter, a csv file will be
+               downloaded to Your System.
+
+    - Import - Upload the csv file in the format given in Sample file and
+              metatags will imported with success and error messages.
+
+**Import CSV file format**
+
+The import CSV file may have the following fields, some combinations of which
+mandatory:
+
+- entity_type - The type of entity. Mandatory unless '`path_alias`' is populated.
+- entity_id - The ID of the entity. Mandatory unless '`path_alias`' is populated.
+- path_alias - The path alias of the entity including the initial '`/`'. Optional.
+- field_machine_name - The machine name of meta tag field on the entity. This
+  field is mandatory.
+- language - The language of the entity translation. Optional.
+
+Other fields are field name of tags.
+
+- Leave a cell empty if you don't want to change the value of that field.
+- Type "`_blank`" if you want to set a value of any field empty.
+
+
+## Requirements
+
+This module requires the following modules:
+
+- [Metatag](https://www.drupal.org/project/metatag)
+- [Token](https://www.drupal.org/project/token)
+
+
+## Installation
+
+Install as you would normally install a contributed Drupal module. For further
+information, see
+[Installing Drupal Modules](https://www.drupal.org/docs/extending-drupal/installing-drupal-modules).
+
+
+## Configuration
+
+1. Configure user permissions in Administration >> People >> Permissions:
+    - Metatag import export csv download - Select the roles you want to give
+            permission to import metatags using the module.
+    - Metatag import export csv upload - Select the roles you want to give
+            permission to export  metatags using the module.
+
+2. Form Page
+    - Metatag-import - The form for metatag import can be accessed by
+                    going to `/admin/config/search/metatag/download`
+    - Metatag-export - The form for metatag export can be accessed by
+                    going to `/admin/config/search/metatag/upload`
+
+## Maintainers
+
+- Joachim Noreiko - [joachim](https://www.drupal.org/u/joachim)
+- Namit Garg - [namit.garg](https://www.drupal.org/u/namitgarg)
+- Aayush Mittal - [aayush23](https://www.drupal.org/u/aayush23)