Missing Aux field in Channel Proposal encryption/decryption

[NhoxxKienn]

Location

client/proposalmsg.go

Problem

The new field Aux of type channel.Aux has been added to BaseChannelProposal. However the encoding/decoding of this type is not yet been added. This will cause the missing of encoded Aux field in Proposals that use perunio.Serializer

Proposal

• Modify Encode/Decode of BaseChannelProposal accordingly.
• Generate the Aux field for randomly generated proposals, that are being used in tests (esp. for VirtualChannelProposal)

[NhoxxKienn]

This issue is related to Issue #1 in perun-vc-hub-service