Start of moving opcodes to storing output in a string

Started with the operation ORI. It stores addresses of strings that will be concatenated to give the final output.

IMPORTANT CHANGES
 - A5 is used to traverse the output string
 - The addresses of the output string start at $5000
 - A6 stores the end of the output string

All of the other operations should still work, as I made new functions for ORI to call.
Merge pull request #30 from cgoodling/new

Start of moving opcodes to storing output in a string