SteppingEventSimulationEngine

1st half of the squashed  https://github.com/openrocket/openrocket/pull/185
original message:
>Hello, we are a group of CS majors and have been working on this as our Senior Capstone project.
>Our goal with the API was to allow for running simulations by use python scripting, or other scripting >methods.
>We have added the API as a way to load an ork file, run a simulation, and retrieve data from the >simulation.
>Additionally, to allow for hardware in the loop testing we have added a stepper that runs the simulation >one step at a time, to allow for real-time data transfer between openrocket and the flight computer of a >rocket.

>The flight computer in our case was av3-fc, and the scripts we wrote to interface between the added api >and the flight computer are here RocketTalk

**SteppingEventSimulationEngine** - A version of BasicEventSimulationEngine that allows for the simulation to be stepped through. (Identical behavior when randomseed is set to a constant)

**FlightDataStep** - (A single step of flight data. One step of data is extracted from a FlightDataBranch object and stored as <key,value> linked hash map in the variable values.) used to retrieve values from a particular simulation step

**CSV Updates** - includes updates to csv file handling to build a csv file as a simulation is being run (line by line updates)

**FlightDataTypes** - Added X, and Y Acceleration to and Storing of those values in the 'extra' sections of the steppers.

**Logger** - Method to change log file location