Web3 id fixes

[shjortConcordium]

Purpose

Some fixes for web3Id stuff, that were missed.

Changes

• verifyWeb3IdCredentialSignature now supports dates/timestamp attributes.
• canProveAtomicStatement now supports timestamp attributes, handles undefined attribute value correctly and handles strings correctly for range statements.
• bump package patch version.

Checklist

• My code follows the style of this project.
• The code compiles without warnings.
• I have performed a self-review of the changes.
• I have documented my code, in particular the intent of the
  hard-to-understand areas.
• (If necessary) I have updated the CHANGELOG