Images section (#813)

* Add new configuration options
* Refactor scan/clean
* Schema changes
* Add details to galleries
* Remove redundant code
* Refine thumbnail generation
* Gallery overhaul
* Don't allow modifying zip gallery images
* Show gallery card overlays
* Hide zoom slider when not in grid mode

pkg/api/urlbuilders/image.go

@@ -0,0 +1,25 @@
+package urlbuilders
+
+import (
+	"strconv"
+)
+
+type ImageURLBuilder struct {
+	BaseURL string
+	ImageID string
+}
+
+func NewImageURLBuilder(baseURL string, imageID int) ImageURLBuilder {
+	return ImageURLBuilder{
+		BaseURL: baseURL,
+		ImageID: strconv.Itoa(imageID),
+	}
+}
+
+func (b ImageURLBuilder) GetImageURL() string {
+	return b.BaseURL + "/image/" + b.ImageID + "/image"
+}
+
+func (b ImageURLBuilder) GetThumbnailURL() string {
+	return b.BaseURL + "/image/" + b.ImageID + "/thumbnail"
+}