Wrong tcx_url

[ronek22]

Hi,
Link to download activity in .tcx format has been changed.
Now it looks like this:
https://flow.polar.com/api/export/training/tcx/1718507404?compress=true
I suggest new way to create tcx_url variable:

idActivity = filter(str.isdigit,str(self.data['url']))
tcx_url = FLOW_URL + '/api/export/training/tcx/' + idActivity + '?compress=true'

[campbellr]

Thanks @ronek22

I don't really use my M400 anymore, so I've been neglecting this library. I'll try to make some time to update it.