[Analyzer] Handle unique_ptr::swap() in SmartPtrModeling

    Summary:
    Implemented modeling for unique_ptr::swap() SmartPtrModeling

    Subscribers: xazax.hun, baloghadamsoftware, szepet, a.sidorin, mikhail.ramalho, Szelethus, donat.nagy, dkrupp, Charusso, martong, ASDenysPetrov, cfe-commits

    Reviewers: NoQ, Szelethus, vsavchenko, xazax.hun
    Reviewed By: NoQ, vsavchenko, xazax.hun

    Tags: #clang

    Differential Revision: https://reviews.llvm.org/D8387