Added automatic dependency sanitizer/finder

Added automatic dependency sanitizer/finder
It is currently a bit rough on the edges, with some unnecessary repetition.
It detects and tries to locate the following:

   Boost header files     -> BOOST_DIR
   SDL2 library files     -> SDL2_DIR
   GLM header files       -> GLM_DIR
   Bullet librar files    -> BULLET_DIR
   Android NDK directory  -> NDK_HOME
   Android SDK directory  -> SDK_HOME
   SDL2 source directory  -> SDL2_SRC_HOME
   SDL2_image directory   -> SDL2_IMAGE_SRC_HOME
   SDL2_mixer directory   -> SDL2_MIXER_SRC_HOME
   SDL2_ttf directory     -> SDL2_TTF_SRC_HOME

    android/initialize_project.sh (-)
    compile.sh
    initialize_project.sh         (+)
    src/SConscript