Improving VM performance.

[Kray-G]

What I am going to do now is:

• Calculating with an integer directly without push. - not done
• Combining instructions of cleanup & store to do it by one operation. - not done
• Combining instructions of cleanup & pop to do it by one operation. - done
• Combining instructions of push & deref to do it by one operation. - not done

These above are not high priority issues because 227f0a6b04fb66411da243b2888cb82af8450736 has got very good result for performance.

If I feel I need it, I will reopen it.

[Kray-G]

some improvement on Windows by 227f0a6b04fb66411da243b2888cb82af8450736. Algorithm changed like direct threading with Visual Studio.