Added functionality to export JSON and JFLAP files.

[jasonma97]

Also contains some starter code for file upload (mainly just the buttons to trigger file upload and the parsing of the file. Haven't gotten to rendering the parsed graph on the screen yet. There are serializations set up for a JSON save, but I wanted to work on adding the different file exports and file upload first. Thus, some of the file exports a hard coded (particularly in the JFLAP output format). Once I get the file upload working, I'll bringing the my code up to par with yours.

[bgrawi]

Hey Jason, looks like a good start, I'll go through and add some comments in the code.