Update README

Author: shimamoto

README.md

@@ -1 +1,49 @@
-# gitbucket-notifications-plugin
+# gitbucket-notifications-plugin
+
+**This plug-in is still experimental.**
+
+This plug-in provides notifications feature on GitBucket.
+
+Plugin version | GitBucket version
+:--------------|:--------------------
+1.0.x          | 4.15.x
+
+## Features
+
+The current version of plug-in provides features such as:
+
+- Pre-included notifications (see below)
+- Watching repositories
+- Subscribing to issues
+
+### Pre-included notifications
+
+GitBucket can send email notifications to users if this feature is enabled by an administrator.
+
+You'll automatically receive these notifications when:
+
+- Opened issues (new issues, new pull requests)
+    - When a record is inserted into the ```ISSUE``` table
+- Comments
+    - Among the records in the ```ISSUE_COMMENT``` table, them to be counted as a comment (i.e. the record ```ACTION``` column value is "comment" or "close_comment" or "reopen_comment") are inserted
+- Updated state (close, reopen, merge)
+    - When the ```CLOSED``` column value is updated
+
+Notified users are as follows:
+
+- individual repository's owner
+- group members of group repository
+- collaborators
+- participants
+
+However, the person performing the operation is excluded from the notification.
+
+### Watching repositories
+
+When you watch a repository, you get notifications.
+You can unwatch a repository to receive notifications when participating.
+If you won't receive any notifications, you select Ignoring.
+
+### Subscribing to issues
+
+You can subscribe or unsubscribe to individual issues.