Parsing of operand, fix some memory issues

The operation from the input line now gets parsed into a instance of
the class BasicOperation.

Made Valgrind happy so far by changing the new[] -statements and
adding some delete[]s.
Basic parsing done

Got basic parsing of lines from the input file that contain an instruction
and its operand (e.g. mov ax, bx) working. Labels etc. not supported yet.

the parseLine() now returns a pointer to an instance of class Instruction,
containing only the c-string data.