Provide tools for directly downloading the datasets from timeseriesclassification.com

[TonyBagnall]

Tools for code based downloading of the datasets would help users access the data.

[TonyBagnall]

this should be a method in DataSetLoading that works with .ts files. It should take the problem name as input and a boolean to indicate if it is after the _TRAIN or the _TEST file. Look first to see if it exists on experiments/data/tsc. If it does, load the data and return. In not, look on TimeSeriesClassification.com/Downloads for the .zip file, extract it correctly to experiments/data/tsc, then load the _TRAIN or _TEST as required