pep 8 formatting. Add root test folder to config
adding the GC bias tools. Bug fixes.
Regorganize color names in arguments. Bug fixes.
Merging typo fixes from Friederike

Merge branch 'master' of https://github.com/fidelram/deepTools
fix xlim issue, changed the way the onePlotPerGroup option plots by now using fig.add_subplot
bug fixes for heatmapper. Default sorting behaviour of computeMatrix was changed to no sorting. Test were updated
adding tests data