Completely remove status reports and date functions

[TinCanTech]

Remove Status Reports:

• show-expire: Shows expration status
• show-revoke: Shows revoked status
• show-renew: Shows renew status

Removed Unused functions:

• ssl_cert_not_before_date()
• ssl_cert_not_after_date()
• iso_8601_cert_startdate()
• iso_8601_cert_enddate()
• iso_8601_timestamp_to_seconds()
• days_to_timestamp_s()
• cert_date_to_timestamp_s()
• db_date_to_iso_8601_date()
• cert_date_to_iso_8601_date()
• read_db()

This change shows how Status Reports code can be removed, in a single step.

[TinCanTech]

Status reports are now re-integrated via easyrsa-tools.lib.

CI test above show correct operation.

[TinCanTech]

Pros: Removes almost one thousand LOC from easyrsa. Cons: None.