[ANN] better-cond 2.1.0

[Mark Engelberg]

https://github.com/engelberg/better-cond

better-cond allows for :let bindings inside of cond, as well as a handful of other goodies that provide for clearer, more readable code by minimizing "rightward drift".

2.1.0 fixes a bug in the handling of pre/post-maps in the defnc macro.