Provide aliases for unicode fields and keywords

I'm thinking of adding aliases for keyword arguments and structure fields that currently require using unicode characters to access. Examples include the σ in the Conv field names, and almost all of the fields in BatchNorm:

julia> fieldnames(BatchNorm)
(:λ, :β, :γ, :μ, :σ, :ϵ, :momentum, :active)

I only have three data points so far, but when other people start to use Flux this has been something that bothers them.

Questions:

• Is this something we should do?
• Would you prefer having ascii names added as aliases, or replacing the current instances of unicode with ascii names and then adding the current unicode names back as aliases?
• Should the ascii name simply spell out the unicode symbol, or describe meaning of the field/variable? For example, should the alias for σ in Conv be activation or sigma? (My preference would be activation.)