Changed EJTimer implementation to work with compiler optimizations.

- Previous implementation only worked with -O0.  When any optimization setting
  other than -O0 was used, some timers with an interval of 1.0 would fire every
  frame instead of every second.  This change resolves that problem and  allows
  timers to work with -O1 and -Os optimization settings.
Merge pull request #10 from wcwynn/ejecta-timer-fix

Changed EJTimer implementation to work with compiler optimizations.