ECG 200 Data loader error and fixed

[huckiyang]

Dear Users,

We get one sincere feedback reported from our user that the ECG 200 dataset was associated with a data loading error.

We have corrected that error and updated our code with the revised result with 85.5% acc.

One current state-of-art performance is Nestor Cabello et al., ICDM 2020 with 90.9% acc.

The other time series does not associate with that error and we have reported the related issues.

Thank you again for all your feedbacks,

V2S team