MM-25095: Handles static JS and CSS using Brotli encoding. (#14524)

* MM-25095: Handles static JS and CSS files using Brotli.

* MM-25095: Linting fix.

* MM-25095: Adds missing license.

* MM-25095: Moves initialization of slice.

* MM-25095: Moves initialization of slice.

vendor/modules.txt

@@ -1,9 +1,6 @@
 # github.com/Masterminds/squirrel v1.2.0
 ## explicit
 github.com/Masterminds/squirrel
-# github.com/NYTimes/gziphandler v1.1.1
-## explicit
-github.com/NYTimes/gziphandler
 # github.com/armon/go-metrics v0.3.0
 ## explicit
 github.com/armon/go-metrics
@@ -239,6 +236,9 @@ github.com/mitchellh/go-testing-interface
 # github.com/mitchellh/mapstructure v1.2.3
 ## explicit
 github.com/mitchellh/mapstructure
+# github.com/mkraft/gziphandler v1.1.2-0.20200509175700-73dc64f3ad90
+## explicit
+github.com/mkraft/gziphandler
 # github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd
 github.com/modern-go/concurrent
 # github.com/modern-go/reflect2 v1.0.1