…#116)

There's no reason to allow for a server to reflect all origin headers.
This has caused numerous security problems in the past.
 - cyu/rack-cors#126
 - https://nodesecurity.io/advisories/148
 - captncraig/cors@cc1cf75

Some helpful blog posts on the topic:
 - https://ejj.io/misconfigured-cors/
 - http://blog.portswigger.net/2016/10/exploiting-cors-misconfigurations-for.html

…lla#122)

This reverts commit 9327cfd.

* added ability to register custom log formatter

* changed function type declaration to work on older versions of Go

* changed to an args struct per PR, refactored logging tests to make it easier to see the scenarios

* fixed formatting and linting issues

* split logging into its own file

* removed writer from the LogFormatterParams struct

* split all logging tests into a separate file

* fixed formatting

gorilla#138)