Develop mca

Hi, Jean-Philippe, could you please test this feature? The function is named SVD().

See merge request !108

Develop configfile

@nmanubens can you please test ASAP?

See merge request !109

Modified config file functions to support for variable tags in the dataset and variable name entries.

Develop downscaleR format

See merge request !107

Develop clusters

@fmassonnet  as the tester for this

See merge request !91