Lots of features, first version that reliably crawls Geminispace.

- [x] Concurrent downloading with workers
- [x] Concurrent connection limit per host
- [x] URL Blacklist
- [x] Save image/* and text/* files
- [x] Configuration via environment variables
- [x] Storing snapshots in PostgreSQL
- [x] Proper response header & body UTF-8 and format validation
.

.

uid/uid.go

@@ -0,0 +1,14 @@
+package uid
+
+import (
+	nanoid "github.com/jaevor/go-nanoid"
+)
+
+func UID() string {
+	// Missing o,O and l
+	uid, err := nanoid.CustomASCII("abcdefghijkmnpqrstuvwxyzABCDEFGHIJKLMNPQRSTUVWXYZ0123456789", 20)
+	if err != nil {
+		panic(err)
+	}
+	return uid()
+}