First cut of -c/—section option for running specific sections

include/internal/catch_interfaces_config.h

@@ -62,6 +62,8 @@ namespace Catch {
         virtual RunTests::InWhatOrder runOrder() const = 0;
         virtual unsigned int rngSeed() const = 0;
         virtual UseColour::YesOrNo useColour() const = 0;
+        virtual std::vector<std::string> const& getSectionsToRun() const = 0;
+
     };
 }