Add "How to" in README:
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HOW To Use
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1. Easy, just like this:
python vimen.py <your_executable_file>
2. In opened VIM window, you can use the following function key:
<F5> start/continue debugging
<F6> toggel break point
<F7> step into
<F8> step over
<S-F7> step out
<C-F8> step until
<S-F5> stop debugging
<F12> set program arguments
3. A Balloon Value Function is also available.
