Merge pull request #42 from lcolladotor/master

Clarify dependencies

Thanks @lcolladotor
Add option to remove the bottom navbar
Render vignettes using knitrBoostrap itself by adding a Makefile to the vignettes dir. Based on https://github.com/lcolladotor/derfinderReport/tree/master/vignettes/Makefile and https://github.com/Bioconductor/BiocCheck/blob/master/vignettes/Makefile