issue #56 WIP - Constants in upper case

duniterpy/api/endpoint.py

duniterpy/constants.py

duniterpy/documents/block.py

duniterpy/documents/certification.py

duniterpy/documents/crc_pubkey.py

duniterpy/documents/document.py

duniterpy/documents/membership.py

duniterpy/documents/peer.py

duniterpy/documents/transaction.py

duniterpy/documents/ws2p/heads.py

duniterpy/grammars/output.py