Review changes made for Issue #53 CMake

I've made all the CMakeList files the project needs. I managed to get the project to build, compile and install. However, when I try to run the qmlscene ui/main.qml, it can't seem to find the directories where the plugins are installed. Could you have a look?
Let's avoid this whitespace noise in this pull request.  If it really bothers you, we can make another just for them.  (Although I prefer to avoid these changes in code from others, in case we want to merge in changes from upstream.)