Fix reported issues

Author: bulislaw

docs/reference/api/platform/PowerManagement.md

@@ -1,6 +1,6 @@
 ## Power management
 
-### Sleep manager
+### Sleep
 
 There is only one sleep function in Mbed OS:
 
@@ -40,6 +40,11 @@ These Mbed OS drivers can lock the deep sleep:
 - `CAN`.
 - `SerialBase`.
 
+#### Example
+
+[![View code](https://www.mbed.com/embed/?url=https://os.mbed.com/teams/mbed_example/code/SleepManager_Example_1/)](https://os.mbed.com/teams/mbed_example/code/SleepManager_Example_1/file/e85412b4147e/main.cpp)
+
+
 ### Idle loop
 
 Idle loop is a background system thread, which scheduler executes when no other threads are ready to run. That may happen when your application is waiting for an event to happen. By default, the idle loop invokes sleep manager to enter a sleep mode. You can overwrite this behavior by providing a different handler: