docs(README): add FAQ: How to deal with assert calls in production

Author: twada

README.md

@@ -140,6 +140,7 @@ FAQ
 - [Cannot capture not invokable method error](https://github.com/power-assert-js/power-assert/issues/36)
 - What is the ['Critical dependencies' warning shown by webpack](https://github.com/power-assert-js/babel-plugin-espower/issues/14#issuecomment-197272436) and how to [suppress warnings](https://github.com/power-assert-js/babel-plugin-espower/issues/14#issuecomment-197909419)?
 - [Causes `TypeError: assert._capt is not a function`](https://github.com/power-assert-js/power-assert/issues/42)
+- [How to deal with `assert` calls in production](https://github.com/power-assert-js/power-assert/issues/43#issuecomment-208851919)
 
 
 EXAMPLE