Java: Plugin Interface, Cryptograpy: Throw exception for encryption / decryption errors.

**Detailed Description**
Encrypt/Decrypt happens at the core-lib level and errors/exceptions are caught and logged on the spot, basically swallowing the exception at the place of call without notifying caller about any errors.

**Actual Behavior**
Steps to reproduce the behavior:
Provide invalid encryption key in .env file to create encryption error or try to decrypt with wrong secret key.
**Expected Behavior**
Errors need to bubble up towards the caller. In the settlement demo example the error need to be caught in the `HCSIntegration` class
**Environment:**
- Java: [e.g. OpenJDK 11.0.4]
- Node: [e.g. v12.9.1-x86]
- OS: [e.g. Ubuntu 18.04]
- Version: [e.g. 1.0.1]

**Additional Context**
Add any other context about the problem here. Attach any logs here, if applicable.