Update context.md

Author: crosschainer

docs/concepts/context.md

@@ -2,7 +2,7 @@
 
 When you are running a contract, you often want to know who is running it. For example, if someone who isn't an account owner tries to spend their money, you need to have some way of identifying who that person is and prevent that from happening. This is where Context, or `ctx` inside of smart contracts, comes into play.
 
-There are five types of `ctx` variables.
+There are six types of `ctx` variables.
 
 | Variable  | Functionality                                           | Details                                                                                                                                                         |
 |-----------|---------------------------------------------------------|-----------------------------------------------------------------------------------------------------------------------------------------------------------------|