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?
Change this to `plugin qhttpserverplugin` to get this module to load correctly.  That's the name used in the CMakeLists file, and it'll be parallel with all the other modules.  (I don't know why I did this one differently.)