I sorted out all the issues introduced due to Travis updating Windows version and adding some changes to the environment, and us updating LibPack. Windows build job now successfully completes the CMake step. In addition and for now i recommend to disable Windows builds, as there is an upstream Travis issue involved, whenever using cmd.exe /C the build will hang and timeout. I did some basic tests with powershell and it looks like the same issue occurs.
P.S. Once this PR gets merged i plan to update the one enabling the useage of ccache for GCC builds and in addition i will create a testing oriented PR, we can use after to detect, when Travis upstream issue gets fixed.