Migrating `map` and `zip` from `Function.Inverse` to `Function.Construct.X`

[Saransh-cpp]

Related to #759

I am planning to move zip and map from Function.Inverse to Function.Construct.X, and I wanted to discuss their new module locations. Function.Construct right now includes Symmetry, Identity, and Composition, but I am not sure which of these files should zip and map be moved to, or if I should create a new file for them.

I also could not entirely understand zip and map. I do understand the standard zip and map but could not really understand the definitions in Function.Inverse.

Thanks!

[JacquesCarette]

The names of map and zip here are, at best, misleading. There's no real structure to map on to. (Well, map is a kind of homomorphism, but surely there's a nicer packaging of this.)

Are these used anywhere?

[Saransh-cpp]

They aren't being used anywhere. Should they just be deprecated and removed, instead of moving them somewhere else?

[JacquesCarette]

That would be my feeling - but let's see what @MatthewDaggitt says.

[jamesmckinna]

We discussed this this morning, but I don't unfortunately recall what our eventual decision was...

[Taneb]

I believe @MatthewDaggitt said he would look into it

[MatthewDaggitt]

Yup agreed. These are just weird, and they don't make much sense in the new hierarchy. Just going to leave them without alternatives and see if we get any complaints.