Extracting common gene-miRNA pairs

The current implementation keeps the duplicate gene and miRNA ids and appends a number at the end of the duplicates using` make.unique()`. The next step is to find the common gene-miRNA pairs between all the tools and regression results. Each of the data frames have gene ids as column names and miRNA ids as row names. The common ids are extracted using the function `common_data()` which uses `Reduce(intersect,lapply(common, rownames))` where `common` is the list of data sets (data frames). This misses out on some ids. For example if df1 has **ENSG1**, **ENSG1.A** and df2,df3,...dfn have only **ENSG1**. This implementation will remove **ENSG1.A** from df1 but it should be kept ideally.