A solution item template that creates a set of default runsettings files under Solution Items, and saves you from having to do this manually. See http://msdn.microsoft.com/en-us/library/vstudio/jj159530.aspx for information on how to change the default settings.
The runsettings file is used to change the code coverage analysis settings for a test run, in particular which files to be included and excluded from analysis, and also used to set symbol search paths. It can also set Runconfigurations and testrunparameters, and specific settings for NUnit and MSTest.
It can also enable parallel run of unit tests.
There are 3 templates included, one complete which includes code coverage and parallel run, one with only code coverage, and one with only parallel run.
See this blogpost for more information :How to exclude code from code coverage in Visual Studio