As per the Visual Studio 2015 feature comparisson between the editions, Microsoft has clearly mentioned that certain features will only be available in Professional & Enterprise editions of VS 2015.
One such feature happens to be the ‘CodeLense’
If you google you can easily find out what’s code lense and its features. This is a good article which explains about code lense (http://www.codeproject.com/Articles/794766/What-is-CodeLens)
This is what has been mentioned in the feature comparisson for Visual Studio 2015 (https://www.visualstudio.com/vs/compare/)
However installing SQL Server Data Tools for VS 2015, will enable this feature in the Community Edition of VS 2015.
SSDT can be obtained from the this site: https://msdn.microsoft.com/en-us/mt186501.aspx
Codel lense feature can be customize using option dialog.
Hope this will be useful to you.