Follow up to r1879080: replace ProxyUseOriginalURI by mapping=encoded.

Follow up to r1879080: replace ProxyUseOriginalURI by mapping=encoded.

Instead of having a separate ProxyUseOriginalURI directive to control pre_ vs
normal translate stage, let's handle this at each ProxyPass level, with the
mapping= parameter.

At pre_translate stage mod_proxy will handle the "encoded" mapping only, and
at translate stage only the others (unless a worker was already elected at
the first stage).

Note that since mapping=servlet needs to happen encoded too, it's defined like:
    #define PROXYPASS_MAP_ENCODED 0x08
    #define PROXYPASS_MAP_SERVLET 0x18 /* + MAP_ENCODED */
so uch that proxy_trans does the right thing.

Follow up to r1879080: replace ProxyUseOriginalURI by mapping=encoded.

Instead of having a separate ProxyUseOriginalURI directive to control pre_ vs
normal translate stage, let's handle this at each ProxyPass level, with the
mapping= parameter.

At pre_translate stage mod_proxy will handle the "encoded" mapping only, and
at translate stage only the others (unless a worker was already elected at
the first stage).

Note that since mapping=servlet needs to happen encoded too, it's defined like:
    #define PROXYPASS_MAP_ENCODED 0x08
    #define PROXYPASS_MAP_SERVLET 0x18 /* + MAP_ENCODED */
so that proxy_trans does the right thing.

This allows for simpler and consistent mapping configuration, where the
translate stage depends only on the mapping= parameter.

To implement a fast path (do nothing) when no encoded mapping is configured
at pre_trans stage, or all mappings are encoded at translate stage, two bits
are added to proxy_server_conf (map_encoded_one:1, map_encoded_all:1) and
updated at load time. Thus MINOR is bumped too.

git-svn-id: https://svn.apache.org/repos/asf/httpd/httpd/trunk@1879145 13f79535-47bb-0310-9956-ffa450edef68