[PATCH] Configurable SSL error details messages

Hi all,

This patch adds support for a translatable and customisable error detail
file (errors/templates/error_details.txt) The file is stored like we
store error page templates today.

Inside the file, an HTTP-like format used that can be
later extended to other error details:

name: value
details: "value"
descr: "value"

or

name: value
details: "multi
      line
      value"
descr: "value with a \"quoted string\" inside"

More informations and some technical details there are in patch preamble.

In this patch also I am including the HttpHeader.cc changes with spaces
changes striped (to make review easier).

This is a Measurement Factory project.