* Sync with 2.2.x and style fixes

  *) mod_rewrite: support rewritemap by SQL query [Nick Kew]

  *) mod_headers: support regexp-based editing of HTTP headers [Nick Kew]

  *) mod_disk_cache: Make caching of large files possible on 32bit machines

     by determining whether the cached file should be copied on disk rather

     than loaded into RAM. PR39380 [Niklas Edmundsson <nikke acc.umu.se>]

  *) mod_cgi and mod_cgid: Don't use apr_status_t error return

     from input filters as HTTP return value from the handler.

     PR#31579.

     PR 31579.  [Nick Kew]

  *) mod_cache: Eliminate a bogus error in the log when a filter returns

     AP_FILTER_ERROR.  [Niklas Edmundsson <nikke acc.umu.se>]

  *) Fix issue which could cause piped loggers to be orphaned and never

     terminate after a graceful restart.  PR 40651.  [Joe Orton,

     Ruediger Pluem]

  *) core: Fix issue which could cause piped loggers to be orphaned and never

     terminate after a graceful restart.  PR 40651.  [Joe Orton, Ruediger Pluem]

  *) Fix address-in-use startup failure caused by corruption of the list of

  *) core: Fix address-in-use startup failure caused by corruption of the list of

     listen sockets in some configurations with multiple generic Listen

     directives.  [Jeff Trawick]

  *) mod_headers: Support regexp-based editing of HTTP headers.  [Nick Kew]

  *) mod_proxy: Add explicit flushing feature. When Servlet container sends AJP

     body message with size 0, this means that Servlet container has asked for

     an explicit flush. Create flush bucket in that case. This feature has been

     added to the recent Tomcat versions without breaking the AJP protocol.

     [Mladen Turk]

  *) mod_proxy_balancer: Set the new environment variable BALANCER_ROUTE_CHANGED

     if a worker with a route different from the one supplied by the client

     had been chosen or if the client supplied no routing information for

  *) mod_disk_cache: Make sure that only positive integers are accepted

     for the CacheMaxFileSize and CacheMinFileSize parameters in the

     config file. PR39380 [Niklas Edmundsson <nikke acc.umu.se>]

     config file. PR39380.  [Niklas Edmundsson <nikke acc.umu.se>]

  *) core: Deal with the widespread use of apr_status_t return values

     as HTTP status codes, as documented in PR#31759 (a bug shared by

     the default handler, mod_cgi, mod_cgid, mod_proxy, and probably

     others). [Jeff Trawick, Ruediger Pluem, Joe Orton]

     others). PR31759.  [Jeff Trawick, Ruediger Pluem, Joe Orton]

  *) mod_ext_filter: Handle filter names which include capital letters.

     PR 40323.  [Jeff Trawick]

  *) mod_isapi: Handle "HTTP/1.1 200 OK" style status lines correctly, the

     token parser worked while the resulting length was misinterpreted.

     PR 29098 [Brock Bland <bbland serena.com>]

     PR 29098.  [Brock Bland <bbland serena.com>]

  *) mod_isapi: Return 0 (failure) for more of the various ap_pass_brigade

     attempts to stream the response at the client.  PR 30022 [William Rowe]

     attempts to stream the response at the client.  PR 30022.  [William Rowe]

  *) mod_isapi: Ensure we walk through all the methods the developer may have

     employed to report their HTTP status result code.

     PR 16637 30033 28089  [Matt Lewandowsky <matt iamcode.net>, William Rowe]

     PR 16637 30033 28089.  [Matt Lewandowsky <matt iamcode.net>, William Rowe]

  *) mod_echo: Fix precedence problem in if statement. PR 40658.

     [Larry Cipriani <lvc lucent.com>]