Query P2P in order to determine if an input is spent later on

[bchamagne]

Description

When retrieving the inputs of an address, we compare them to the inputs of the latest transaction of the address.
If an input has a match (the same (token, from)) in the last transaction, that input is unspent. If there is no match for an input, it means it has been spent.

Fixes #627

Type of change

• Bug fix

How Has This Been Tested?

This has been tested via integration tests and with the following scenario on the explorer:

1. Bastien creates a CC token
2. Bastien creates a DD token
   
3. Bastien transfers some DD token to Hamza
   

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules