makefile now supports easier adding of additional source files and has a clean target
use ftell instead of fgetpos, since fpos_t returned by fgetpos is NOT a simple integer on RPi
added stub with empty implementations of platform dependant glContext parts. Currently, the setup code is wholly contained in esUtil, so Context doesn't need to do anything at all
added missing currentTimeSeconds()
added RPi to number of supported GL ES platforms
added calls to lost::Engine in a very basic manner, for testing purposes
tweaked test display a bit, removed Mesh cloning of interpolated points to produce massive performance boost
added missing sources and include paths