Multiple test adapters in TFS 2013 build

Question

I am developing a software that contains multiple solution and uses:

• Nunit Test Adapter: C# Solution
• Boost Test Adapter: C++ Solution

until now what i am doing is use a version control path to custom assemblies, I have tried to decompress both of the test runners there (this is messy).

Of course i will then have two definitions of test that run.Again this causes some issues because i have two test adapters in the same folder.

The questions i will like to ask are:

• Is there anyway to organize this better than the path to custom assemblies?
• Is there a way of specify what test runner to use?
  • I have though about .runsettings. Is this the correct way?, is there any
    example for nunit test adapter?

all this is for TFS 2013, TFS 2015 seems to have really improved this.