Introduce QueryParams for use in rest endpoints (disgoorg#403)

* Introduce QueryParams for use in rest endpoints

* add "docs" lol

Author: sebm253

rest/query_params.go

@@ -0,0 +1,11 @@
+package rest
+
+import (
+	"github.com/disgoorg/disgo/discord"
+)
+
+// QueryParams serves as a generic interface for implementations of rest endpoint query parameters.
+type QueryParams interface {
+	// ToQueryValues transforms fields from the QueryParams interface implementations into discord.QueryValues.
+	ToQueryValues() discord.QueryValues
+}