sharing: extend doc

DOCUMENTATION.md

@@ -726,6 +726,12 @@ _(>= 3.6.0)_
 
 Verification of a particular item file
 
+##### --verify-sharing
+
+_(>= 3.7.0)_
+
+Verification of local sharing database
+
 ##### -C|--config <file>
 
 Load one or more specified config file(s)
@@ -2043,6 +2049,49 @@ is thrown instead of returning the results.
 
 Default: 10000
 
+#### [sharing]
+
+_(>= 3.7.0)_
+
+##### type
+
+_(>= 3.7.0)_
+
+Sharing database type
+
+One of:
+ * `none`
+ * `csv`
+ * `files`
+
+Default: `none` (implicit disabling the feature)
+
+##### database_path
+
+_(>= 3.7.0)_
+
+Sharing database path
+
+Default:
+ * type `csv`: `(filesystem_folder)/collection-db/sharing.csv`
+ * type `files`: `(filesystem_folder)/collection-db/files`
+
+##### collection_by_token
+
+_(>= 3.7.0)_
+
+Share collection by token
+
+Default: `false`
+
+##### collection_by_map
+
+_(>= 3.7.0)_
+
+Share collection by map
+
+Default: `false`
+
 ## Supported Clients
 
 Radicale has been tested with: