setup: export functions and variables for external packages.

Tests for config/setup/internal.go

Tests for config/setup/log.go

fastcgi: fix #127

ext: test for function extParse

log: ensure the correct status is always logged

in the case of error (>=400) then no response may have been sent

Preliminary test case for setup/config/ext.go

Update with missing assertion for the Next middleware being properly set , this makes sure that Ext middleware carries the requests to the further middlewares .

Added assertions to check for the extensions in the order specified

middleware: let middleware.responseRecorder be a http.Hijacker

Signed-off-by: Tw <tw19881113@gmail.com>

Gzip: Accept MIME types.

fixes issue with Status header coming from php-fpm 5.5 different then regular "HTTP/1.1 200 OK".
If server returns  Status code - "200" will be handled properly instead "throwing runtime error: index out of range"

internal: rename middleware's package name from `internal` to `inner`

redirect: add ability to do meta redirects

The internal package has the special meaning in go
(see https://golang.org/s/go14internal).
So rename it to `inner`.
Signed-off-by: Tw <tw19881113@gmail.com>

Proper Location redirects are disadvantageous in some situations.
For example, you may want a developer to know that a resource is available
via https, but you don't want an insecure call to the API to succeed.

Update error strings (start with lowercase letters)