Fixed typo

README.md

@@ -91,7 +91,7 @@ To enable automatic Time Activity entries for an Issue, you simply need to assig
 
 **Note:** After the initial synchronization, this plugin will receive push notifications via Intuit's webhook service.   
 
-## Comainion Plugin Hooks
+## Companion Plugin Hooks
 * :pdf_left, { issue: issue }
 * :pdf_right, { issue: issue }
 * :process_invoice_custom_fields, { issue: issue, invoice: invoice }