Continued to add symbol support.

Continued to add symbol support.

Moved load_symbols code into main function.
Added reset_buffer function that moves current_command
pointer back to beginning of input buffer. This was
required as the has_more_commands and advance functions
are now used to travel through the code twice.

Function enc_symbol now passes an integer value instead of
an array of type char.

Function symbol no longer requires an array. Now converts chars
into an integer and returns int value to caller.

New function symbol_load pushes symbols into the hash array.
Uses new rom_address as location for symbol.

Address for RAM has been created, but not fully implemented.