Use validator library to validate timestamp offset value

[rkpattnaik780]

Description

Version: 0.31.0

Use an iso8601 validator lib to validate value provided for timestamp input.

Originally discussed here.

[wtrocki]

More info is needed for community to pick that up. (Where to change and what package to use)

[alexal]

@wtrocki I would like to work on this. Please assign this issue to me.

[wtrocki]

@alexal With broken heart I need to close that PR unmerged. We would need to introduce our own parsing format.
Apologies for not including this.