Update README.md

Added API Polling link

README.md

@@ -16,7 +16,7 @@ pdfRest is a REST API Toolkit for developers with all of the API Tools you'll ne
 **[Query PDF](https://pdfrest.com/apitools/query-pdf/)**           | **[Linearize PDF](https://pdfrest.com/apitools/linearize-pdf/)**   | **[Upload Files](https://pdfrest.com/apitools/upload-files/)**                   | **[Zip Files](https://pdfrest.com/apitools/zip-files/)**
 | **[Flatten Forms](https://pdfrest.com/apitools/flatten-forms/)** | **[Import Form Data](https://pdfrest.com/apitools/import-form-data/)** | **[Export Form Data](https://pdfrest.com/apitools/export-form-data/)** | **[Extract Text](https://pdfrest.com/apitools/extract-text/)** |
 | **[PDF to Word](https://pdfrest.com/apitools/pdf-to-word/)** | **[PDF to Excel](https://pdfrest.com/apitools/pdf-to-excel/)** | **[PDF to PowerPoint](https://pdfrest.com/apitools/pdf-to-powerpoint/)** | **[Convert PDF Colors](https://pdfrest.com/apitools/convert-pdf-colors/)** |
-| **[OCR to PDF](https://pdfrest.com/apitools/ocr-pdf/)** | | | |
+| **[OCR to PDF](https://pdfrest.com/apitools/ocr-pdf/)** | **[API Polling](https://pdfrest.com/apitools/api-polling/)** | | |
 
 <br>