Created basic input parser

Created a basic input parser which accpets input one word at a time
and then echos the first character of the word back to the user.

* main.cpp - Created input parser.

* deliverables/log.md - Updated progress log.
Added operand parsing

Added the ability to distinguish operands from operators. Operands
are pushed onto the operand stack, while operators are merely
echoed. Then the current state is outputed.

* main.cpp - Added operand parsing and operand stack.

* deliverables/log.md - Updated progress log.