Update Readme.txt

Author: AlfredStenwin

Readme.txt

@@ -21,3 +21,5 @@ Jackson library is used for reading the csv and json files. The utility classes
 Only 3 sample tests are added now to give an idea of how to write the test cases but there are plans to add more test cases to give the users a better idea of the framework. 
 
 Framework can be easily extended to use Appium for Android / iOS or Windows based apps using WinAppDirver by adding the respective drivers and capabilities in the driver factory. Also add the dependencies in the pom.xml file
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+Note: Even though perallel execution is supported by Selenium and TestNG, it is not supported in current form of this framework. To run in parallel, ThreadLocal should be used to make it thread-safe. But since the decorator pattern is used to support logging, parallel run will cause errors.