define_model_rf: define and save model
In rte-antares-rpackage/antaDraft: clean and validate entsoe datasets

create a model for each country of an validated and corrected load dataset. Each model is saved in a file.

1 2	define_model_rf(data, x_vars, y_var, save_model_dir = getwd(), id = "", h2o_port = 54321, h2o_ip = "localhost")

`data`	aggregated load dataset
`x_vars`	x variables
`y_var`	y variable
`save_model_dir`	directory where to save models
`id`	models id, will be used to prefix files and qualify produced models
`h2o_port`	port number of the H2O server
`h2o_ip`	IP address of the server where H2O is running