Fixed large server timing headers breaking proxies.

Fixes #40

CHANGELOG.md

@@ -12,6 +12,7 @@ and this project adheres to [Semantic Versioning](http://semver.org/).
 ### Fixed
 - Mustache.php version to resolve issues on PHP 7.4
 - type crash when URL passed to network request filters is invalid
+- large server timing headers breaking proxies
 
 ## 3.3.1 - 2019-07-02