Revert "set http.Client.Timeout in net2/http2.SimplePool if supported (>= go-1.3)"
Revert "set http.Client.Timeout in net2/http2.SimplePool if supported (>= go-1.3)"

This reverts commit 02ef46632aff5043f912d3eb40ccdf9b65cff691.

horryq/godropbox,icattlecoder/godropbox,pattyshack/godropbox,zj8487/godropbox,cch123/godropbox,zj8487/godropbox,horryq/godropbox,sixolet/godropbox,sixolet/godropbox,horryq/godropbox,gc-locks/gosqlbuilder,wfxiang08/godropbox,danielrh/godropbox,pattyshack/godropbox,abduld/godropbox,cch123/godropbox,zj8487/godropbox,dropbox/godropbox,wangtuanjie/godropbox,wfxiang08/godropbox,wfxiang08/godropbox,abduld/godropbox,icattlecoder/godropbox,danielrh/godropbox,icattlecoder/godropbox,danielrh/godropbox,dropbox/godropbox,wangtuanjie/godropbox,wangtuanjie/godropbox,abduld/godropbox,sixolet/godropbox,cch123/godropbox,dropbox/godropbox,pattyshack/godropbox