objectPath.modify

[seggev319]

objectPath.modify: Modifies an existing value using a provided function

[coveralls]

Coverage decreased (-0.6%) to 99.171% when pulling 1348d08 on seggev319:patch-1 into 99d9d30 on mariocasciaro:master.

[j-rewerts]

I could see this being useful. Is there any interest in having this functionality as part of the package @mariocasciaro ?

[mariocasciaro]

It's better if the function is called update to mirror the same function in object-path-immutable. Also we would need some unit tests, before we can commit.

[j-rewerts]

I can make these on a separate PR.