Removal of legacy indy-sdk crates and dependencies

[JamesKEbert]

The indy-sdk has been deprecated in favor of multiple shared components (Aries Askar, anoncreds-rs, indy-vdr), which are already supported within Aries VCX via feature flags. The Aries VCX maintainers would like to remove these crates and the usage of indy-sdk in any of its forms in Aries VCX. This includes the removal of:

• /misc/legacy/indyvdrtools (essentially a modified fork of indy-sdk) -- replaced by aries-askar for storage requirements
• AnonCreds support via credx -- replaced by anoncreds-rs
• vdrtoolswallet (indy-sdk wallet) to aries-askar wallet migrator -- no longer necessary

This does not include the removal of the traits/interfaces in front of these tools--this will enable easier development of future implementations for different use cases while having common interfaces (different storage options or WASM compatible implementations for instance).

According to our present knowledge, these proposed crates/feature flags/tools to be removed were only being consumed by Absa, and Absa is no longer involved in the project.

If any of these tools are important to your project or use case please let us know below, or reach out to one of the Aries VCX maintainers directly.

[gmulhearn]

This would remove a lot of repo bloat. Excited for this transition 👍