DPCat Docs fix transposed words

Author: Willmac16

Svc/DpCatalog/docs/sdd.md

@@ -2,7 +2,7 @@
 
 ## 1 Introduction
 
-`DpCatalog` is an active F´ component that manages the downlink of generate data products. The data products were previously generated by components into a project-specific set of directories. Upon command, `DpCatalog` will build a catalog of data existing products and start downloading them. They are downloaded based on a priority stored in the file and by generation time. `DpCatalog` also has commands to reprioritize and delete data products.
+`DpCatalog` is an active F´ component that manages the downlink of generate data products. The data products were previously generated by components into a project-specific set of directories. Upon command, `DpCatalog` will build a catalog of existing data products and start downloading them. They are downloaded based on a priority stored in the file and by generation time. `DpCatalog` also has commands to reprioritize and delete data products.
 
 NOTE: This release has an early prototype that will do the following: