Add XML documentation for Org.Apache.Http.Client.Params

[jonathanpeppers]

The Org.Apache.Http.Client.Params namespace contains 60 To be added placeholders in source XML documentation (excluding docs\xml\index.xml).

rg -n -i --glob 'Org.Apache.Http.Client.Params/**' --glob 'ns-Org.Apache.Http.Client.Params.xml' 'to be added' docs\xml