Hello! I got tired of manually changing everything every time I started a new project, so I've created a template for VS 2015 for RimWorld mods.
Download: http://merthsoft.com/RimWorldMod.zip (http://merthsoft.com/RimWorldMod.zip)
Just plop that into
C:\Users\<username>\Documents\Visual Studio 2015\Templates\ProjectTemplates and you'll be able to go to New Project -> RimWorldMod:

Make sure you create it in the Mods folder of your RimWorld install, so for steam:
C:\Program Files (x86)\Steam\SteamApps\common\RimWorld\Mods. It uses relative addressing for the references, so should be alright for non-Steam as well. If anyone wants to add this to a wiki or tutorial or whatever, feel free.
Edit: Maybe this should be in the tools subforum? I can't move it, though.
Tried this out, it's pretty convenient. Thanks!