copy_includes -> prepare_psol
duplicate-headers: prevent some headers from being copied over

Amongst other headers, don't copy the "Connection" response-header
when we receive it from psol.

Combined with our config trick[1] to prevent add_header from setting
any other headers should fix

[1] location ~ ".pagespeed.([a-z].)?[a-z]{2}.[^.]{10}.[^.]+" {
add_header "" "";
}
readme: update Page-Speed version
Merge pull request #321 from pagespeed/oschaaf-duplicate-headers

duplicate-headers: prevent some headers from being copied over
small cleanup: stale comment, confusing log message
Merge pull request #322 from pagespeed/oschaaf-small-cleanup

small cleanup: stale comment, remove confusing log message
beacons: serve as `Cache-Control: max-age=0, no-cache`
Merge pull request #323 from pagespeed/jefftk-no-cache-beacon

beacons: serve as `Cache-Control: max-age=0, no-cache`
random-hangs: attempt to fix random hangs
Merge pull request #333 from pagespeed/oschaaf-fix-random-hangs

random-hangs: attempt to fix random hangs
static-handler-etag: emit an etag in responses from our static handler

Fixes the etag part of https://github.com/pagespeed/ngx_pagespeed/issues/212
gzip-and-etags: prevent gzip from clearing our weak etags
static-handler: fix compression
Updated README.md: nginx-1.4.1 stable

nginx-1.4.1 includes an important security fix
More details: http://nginx.org/en/CHANGES-1.4
Merge pull request #346 from patschi/patch-3

Updated README.md: nginx-1.4.1 stable
Merge pull request #344 from pagespeed/oschaaf-static-handler-fix-compression

static-handler: fix compression
Merge pull request #343 from pagespeed/oschaaf-static-handler-etag

static-handler-etag: emit an etag in responses from our static handler
style: prefix a few names with ps_
Merge pull request #348 from pagespeed/oschaaf-rename-write-handler-response

style: prefix a few names with ps_
native-fetcher: fix host header handling when no host header is given

When the host header is not explicitly set in the request headers that
are passed in, the native fetcher needs to derive it from the url.

Fixes https://github.com/pagespeed/ngx_pagespeed/issues/347