Special currying 

All within `+-` of each other. I have other ones ready locally if this floats your boat
http://jsperf.com/ramda-auto-curry-cost/10

Optimizations are potentially possible by switching the switch with a lookup or if?
Also, this one and `remove` are clearly missing some tests, or this refactoring would have broken.  They both need `curry3` wrappers.  You got it for `insert.all`; obviously the same applies here.