This fixes local build.rs script not running correctly due to changed folder structure. Also moved crypto-shared folder into chain-signatures since that would be annoying later to deal with.
Show Destroy Plan
```
No changes. No objects need to be destroyed.
Either you have not created any objects yet or the existing objects were
already deleted outside of Terraform.
Destroy complete! Resources: 0 destroyed.
```
This fixes local build.rs script not running correctly due to changed folder structure. Also moved
crypto-shared
folder intochain-signatures
since that would be annoying later to deal with.