docs(README): add Incomplete increment/decrement assertion messages? to README

refs #32

Author: twada

README.md

@@ -136,6 +136,7 @@ FAQ
 - [Does this work with substack/tape?](https://github.com/power-assert-js/power-assert/issues/30)
 - [Are all dependencies required at runtime?](https://github.com/power-assert-js/power-assert/issues/24)
 - [Descriptive assertion message does not appear when writing tests in ES6 with Babel](https://github.com/power-assert-js/webpack-espower-loader/issues/4#issuecomment-139605343)
+- [Incomplete increment/decrement assertion messages?](https://github.com/power-assert-js/power-assert/issues/32)
 
 
 EXAMPLE