hd-only: add 2fa support

src/Jackett.Common/Definitions/hdonly.yml

@@ -39,6 +39,13 @@ settings:
   - name: password
     type: password
     label: Password
+  - name: 2fa_code
+    type: text
+    label: 2FA code
+  - name: info_2fa
+    type: info
+    label: "About 2FA code"
+    default: "Only fill in the <b>2FA code</b> box if you have enabled <b>2FA</b> on the HD-Only Web Site. Otherwise just leave it empty."
   - name: freeleech
     type: checkbox
     label: Search freeleech only
@@ -88,6 +95,7 @@ login:
   inputs:
     username: "{{ .Config.username }}"
     password: "{{ .Config.password }}"
+    twofa: "{{ .Config.2fa_code }}"
     keeplogged: 1
   error:
     - selector: form#loginform > span.warning