Use Unix timestamp for start and end in Metadata

[tinypell3ts]

I think we should store start and end time as a unix timestamp. This will allow us to remove the date from the metadata. The frontend can work out the date from the timestamps.

e.g.
Start - 1652276545 (Wed May 11 2022 13:42:25 GMT+0000)
End - 1652362945 (Thu May 12 2022 13:42:25 GMT+0000)

[ruarim]

yup i agree.
How/Where would we store it? On the contract?