Unable to create maps where the source is an array

[pleek91]

Issue

Since mapper.map automatically maps over arrays we're unable to create maps that take the entire array as a source. Which means we cannot write mappers to convert an array to an object which is quite useful.

Proposal

Separate out array mapping into a separate method similar to mapEntries. Possibly mapArray. And update map to only work on single values.

Breaking Change

Doing this would be a breaking change since many of our mappers rely on mapper.map accepting an array and mapping over each value individually.

Unknowns

Will the types work correctly?