Move documentation into Documentation/ and format with asciidoc

The Makefile produces simple HTML files from the input,
by passing everything through the asciidoc tool chain.

Signed-off-by: Shawn O. Pearce <sop@google.com>

Documentation/config-gitweb.txt

@@ -0,0 +1,43 @@
+Gerrit2 - Gitweb Integration
+============================
+
+Gerrit2 can generate hyperlinks to gitweb, allowing users to jump
+from Gerrit content to the same information, but shown by gitweb.
+
+To enable the gitweb integration, update `system_config.gitweb_url`
+with the URL of your gitweb CGI.
+
+The CGI's `$projectroot` should be `git_base_path`, or a fairly
+current replica.  If a replica is being used, ensure it uses a full
+mirror, so the `refs/changes/*` namespace is available.
+
+====
+  psql -c "UPDATE system_config SET gitweb_url='http://example.com/gitweb.cgi'" reviewdb
+====
+
+After updating `system_config`, the Gerrit server must be restarted
+and clients must reload the host page to see the change.
+
+gitweb_url
+----------
+
+Defines the web location where a `gitweb.cgi` is installed to browse
+`git_base_path` and the repositories it contains.
+
+Gerrit appends any necessary query arguments onto the end of this URL.
+For example, "?p=$project.git;h=$commit".
+
+Access Control
+--------------
+
+Gitweb access controls can be implemented using standard web server
+access controls.  This isn't typically integrated with Gerrit's own
+access controls.  Caution must be taken to ensure the controls are
+consistent if access needs to be restricted.
+
+Caching Gitweb
+--------------
+
+If your repository set is large and you are expecting a lot
+of users, you may want to look at the caching forks used by
+high-traffic sites like kernel.org or repo.or.cz.