update docs for new options

README.md

@@ -72,6 +72,22 @@ suo.lock do |token|
 end
 ```
 
+### Time To Live
+
+```ruby
+Suo::Client::Redis.new("bar_resource", ttl: 10) #ttl in seconds
+```
+
+All locks are expired and the lock key is removed after the specified `ttl` time runs out. This would be the time since any resource for a given key was locked or unlocked.
+
+### Lock Release Removes Key
+
+```ruby
+Suo::Client::Redis.new("bar_resource", lock_release_removes_key: true)
+```
+
+Normally, a key representing a set of resource locks is persisted indefinitely even when no resources are currently locked. When `lock_release_removes_key` is set to `true`, the key is removed when the last resource lock is released. This also means that when another lock is acquired the key has to be recreated.
+
 ## TODO
  - more race condition tests