Refactoring execution.

README.md

@@ -421,7 +421,7 @@ This will start the following program/nodes:
 - A resource node that keeps tracks of locking.
 - TST Exec Factory: A factory that creates and stores the TST trees used for execution.
 - Basic Executors: Starts executor factories for: seq, conc, wait, noop, test_if, supp and send_signal.
-- Executor Manager: Helps with execution of started executors.
+- Tree executor: The programs that handles the execution of a TST tree.
 - A  world database and coordinate conversion functionality.
 
 ### 2.2.2 Start TST display server (ROS2)