Changes in the option format of makeBDTEff

Moved some options of makeBDTEff from the command line to a config file.

This is because in the analysis workflow, the bdt cut valued are only parsed into config files, and it would be difficult to pass these values to the command line for the previous version of the makeBDTEff script. So, now the cut (but also some other options, for convenience) are now read from a simple config file.

Update of the readme.