Refactor Filter options into a struct

It was already a lot of options for one method and I am going to add
another one in the next commit.

api/api.go

@@ -227,8 +227,13 @@ func showPackages(c *gin.Context, reflist *deb.PackageRefList, collectionFactory
 
 		list.PrepareIndex()
 
-		list, err = list.Filter([]deb.PackageQuery{q}, withDeps,
-			nil, context.DependencyOptions(), architecturesList)
+		list, err = list.Filter(deb.FilterOptions{
+			Queries:           []deb.PackageQuery{q},
+			WithDependencies:  withDeps,
+			Source:            nil,
+			DependencyOptions: context.DependencyOptions(),
+			Architectures:     architecturesList,
+		})
 		if err != nil {
 			AbortWithJSONError(c, 500, fmt.Errorf("unable to search: %s", err))
 			return
@@ -244,8 +249,9 @@ func showPackages(c *gin.Context, reflist *deb.PackageRefList, collectionFactory
 				fmt.Println("filter packages by version, query string parse err: ", err)
 				c.AbortWithError(500, fmt.Errorf("unable to parse %s maximum version query string: %s", p.Name, err))
 			} else {
-				tmpList, err := list.Filter([]deb.PackageQuery{versionQ}, false,
-					nil, 0, []string{})
+				tmpList, err := list.Filter(deb.FilterOptions{
+					Queries: []deb.PackageQuery{versionQ},
+				})
 
 				if err == nil {
 					if tmpList.Len() > 0 {