I downloaded and installed the Microsoft Connector for Oracle by Attunity from the following location for VS 2015 to use with SQL Developer 2014:
https://www.microsoft.com/en-us/download/details.aspx?id=44582
It installed correctly, but for some reason I cannot find it in VS 2015.
The following post shows where to find it in another version of VS under some SSIS tabs when adding new toolbox controls:
Attunity SSIS not available in SSIS Data Flow Tasks
But those tabs don't exist in VS 2015.
I also tried to just right-click in various areas in the SSIS toolbox to "Refresh Toolbox" and to add the Attunity "dll" I found under the install folder, but neither worked.
No SSIS tab:
Adding the "dll" file
I figured out the problem through the help of a Microsoft team member. The answer is you need to install all the correct Attunity versions 3.0, 4.0, and 5.0. There aren't any clear instructions that tell you that, but you do. Also, make sure you change the project compatibility to SQL Server 2014 when using Visual Studio Community 2015. By default it uses SQL Server 2016 mode.