started working on the engine-user interface and refactored code to have things clean ^^

added updateable interface
OakVR is now a static lib; this will let the user have his own executable(need to check dependencies; for now the user needs to link to opengl libs from his project)
mouse input doesn't use low-level-hook anymore in order to prevent stutter in debug mode
added a new project, Construct, which will be our test bench