Currently there is a half and half situation where the user can't use regex (fully) because * will be replaced with (.*), yet they also can't just enter any old string, because meta chars like . would need escaping.
e.g. currently *.html wouldn't work as intended, and instead *\.html should be used.
Work around this by using regexp's QuoteMeta function to sanitise the input before handling it.
This reintroduces support for Go modules, as v4.
CloseNotifier() is removed as it has been obsoleted, see https://golang.org/doc/go1.11#net/http
It was already NOT working (not sending signals) as of 1.11 the functionality was gone, we merely
deleted the functions that exposed it. If anyone still relies on it they should migrate to using
`c.Request().Context().Done()` instead.
Closes#1268, #1255
