Remove Datetime

[peterdudfield]

Detailed Description

Datetime feastures are being made in data_loader on the fly, therefore can remove them here

Possible Implementation

Delete Datetime model in Batch, porbably can remove folder in data_sources/datatime

[JackKelly]

Ah, yes, just to clarify (although I'm sure you know this already!)

We should remove the sin and cos datetime features.

We should still leave the datetime fields in the NetCDF files though (so nowcating_dataloader knows the precise datetimes of each timestep)

BTW, unless I've misunderstood, I think this new issue might be a duplicate of #208 ?

[peterdudfield]

Yea its a duplicate - sorry