Add component diagram

Author: dboltovskyi

assets/proposals/NNNN-atf-script-runner/atf_script_runner_diagram.png

@@ -7,7 +7,7 @@
 
 ## Introduction
 
-ATF is a great tool for both developers and testers that help test any change in SDL.
+ATF is a great tool for both developers and testers that helps to test SDL functionality.
 But it lacks a powerful test script runner.
 
 ## Motivation
@@ -18,24 +18,32 @@ Currently ATF is unable to:
   - run test script in parallel
   - create test reports in standard format
 
+The purpose of this proposal is to develop extended script runner as part of ATF package.
+
 ## Proposed solution
 
-The purpose of this proposal is to develop extended script runner as part of ATF functionality with the following features:
+Script runner is a command line tool with the following features:
 
   - An option to run single test script
   - An option to run batch of test scripts
   - An option to run test set
   - Possibility to run test scripts in parallel (in separate threads)
   - Ability to create reports with logs collected in a format used by continuous integration system
 
+Input data could be defined as a set of input parameters and options.
+
+![Component relations](../assets/proposals/NNNN-atf-script-runner/atf_script_runner_diagram.png)
+
+Functionality of 'SDL Watchdog' and 'ATF Facade' is described in other proposals.
+
 ## Potential downsides
 
 N/A
 
 ## Impact on existing code
 
-No impact on existing code is observed.
+No impact on existing code is observed since script runner is a new module.
 
 ## Alternatives considered
 
-Refactoring of existing runner, but it will negotiate current big base of test artifacts
+Refactoring of existing runner (bash script), but it will negotiate current big base of test artifacts.