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?
Here's what I added to get the textures working:
```
set(IMAGE_SRC
    images/stainedpaper_tiled.jpg
)

add_custom_command(OUTPUT Textures.qml
     COMMAND ./encoder.sh ${IMAGE_SRC} > ${CMAKE_CURRENT_BINARY_DIR}/Textures.qml
     WORKING_DIRECTORY ${CMAKE_CURRENT_SOURCE_DIR}
     DEPENDS ${IMAGE_SRC}
)
add_custom_target(MakeTextures ALL DEPENDS Textures.qml)
```