Added command_prompt and historybuffer
Merge pull request #7 from darklord1310/master

Added command_prompt and historybuffer
Make the PAGEUP and PAGEDOWN can remember the last input
Merge pull request #8 from darklord1310/master

Make the PAGEUP and PAGEDOWN can remember the last input
Merge pull request #9 from mygamelife/master

Done merging NumberToken, OperatorToken files and added some of the file