clock initialization() and new_frame()
imported clock class into SandboxGame
changed window update to use the clock

Previously, the ship position over time depended on the time to render
the frame.  The ship position over time is now dependent on the clock
class' calculated delta time.

Even with the lag spike that simulates a long calculation time between
frames, the ship's new position at drawing time is dependent only on the
clock and will appear where we expect it as if the lag spike had not
occurred.
moved an errorneously-placed file

I accidentally put the vector2D testing code in the Engine project
instead of the EngineTester.  I moved the file.
added basic keyboard input
changed to simultaneous multiple key inputs
changed to acceleration-based velocity
some cleanup

I was getting compiler warnings about a performance issue in the clock
in converting the int return value of the query functions to a bool.  I
changed the code to be a true boolean comparison.

I also got a compiler warning that including .h files from the Qt
include\Qt\ directory was depreciated.  I changed to using their
equivalent non-header versions, and the warning went away.