Allow for API user to change the amount of mods responded with in search (#61)

* Add more info to search route:

* Run formatter

* Allow for API user to change the amount of mods responded with in search

* Refactor SearchResults

* Fix searchresults usage

src/models/mods.rs

@@ -130,4 +130,5 @@ pub struct SearchRequest {
     pub version: Option<String>,
     pub offset: Option<String>,
     pub index: Option<String>,
+    pub limit: Option<usize>,
 }