Add prerequisites and units tests
R/calculate_intensity.R: Added a TODO in prepareBamFiles function

Signed-off-by: Charles Joly Beauparlant <Charles.Joly-Beauparlant@crchul.ulaval.ca>
Merge branch 'master' of https://github.com/adeschen/MetaFeatures
Changed the name of the prepareRegions function to prepareFeatures in main code and in unit tests

Signed-off-by: Charles Joly Beauparlant <Charles.Joly-Beauparlant@crchul.ulaval.ca>
R/calculate_intensity.R: added the scaleVector function

Signed-off-by: Charles Joly Beauparlant <Charles.Joly-Beauparlant@crchul.ulaval.ca>