diffnet.r: changes in documentation; changes in plot.diffnet
renamed gs_func.R to ggmgsa.R
Some changes:
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* diffnet.r: documentation improved
* ggmgsa.r: new names for functions
* diffnet_ex.r: very minor change
 Some changes
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* ggmgsa.R: improved documentation, changed names of output variables
* auxfunc.R: very minor change
Merge branch 'master' of https://github.com/FrankD/NetHet