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generate MS02 null model
 use switch to control the number of ms02 nulls
 output them into separate files in an optional output directory
 output them into one file separate by FASTA header

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Things to do:
 Class diagram; member variables table


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Programs to do:
-add random noise to nodes
-add random noise to edges without affect node's degree (partial ms02) 
-on average, how many edges are still remained after ms02 shuffling?

-inverse node and edge for category analysis

-use R function to call ms02, count edges, do Z-score calculation etc.
