first attempt at making simulink optional.  call simulateODE when possible.  will probably have to sprinkle checkDependency('simulink') into a lot of places
removed spotless from being mandatory
poly in coordinate frame is only produced as needed (this dramatically reduces the dependency on spotless)
pass unit tests
fix unit tests
fix some overly aggressive find and replace for poly -> getPoly
finally figured out the last bug.  that was a subtle one
resolves #412
minor edits from code review
Merge pull request #410 from RussTedrake/sans_simulink

major cleanup of dependencies