fixes #286 nng_pair0_open (and all others) need man page

fixes #279 consider restructuring man sections

This represents a rather significant rework, and major editing
effort, for the entire set of manual pages.

All of the pages now have a section number in their filename;
this assists in some other tooling, particularly ebook generation
as every link needs to be programmatically modified when combined
into an ebook.

Section 5 is introduced, and populated with pages for the main
types, and all options are now documented.

Numerous errors have been corrected, including rewriting certain
portions such as the header section of the surveyor protocol.

Much work has been done to facilitate index generation, although
certainly more work remains here.

Every internal link within these pages now resolves; there are no
more dead links.  (This is required to generate Kindle format books.)

1 files changed, 57 insertions, 0 deletions

diff --git a/docs/man/nng_http_server_add_handler.3http.adoc b/docs/man/nng_http_server_add_handler.3http.adoc
new file mode 100644
index 00000000..489489b1
--- /dev/null
+++ b/docs/man/nng_http_server_add_handler.3http.adoc
@@ -0,0 +1,57 @@
+= nng_http_server_add_handler(3http)
+//
+// Copyright 2018 Staysail Systems, Inc. <info@staysail.tech>
+// Copyright 2018 Capitar IT Group BV <info@capitar.com>
+//
+// This document is supplied under the terms of the MIT License, a
+// copy of which should be located in the distribution where this
+// file was obtained (LICENSE.txt).  A copy of the license may also be
+// found online at https://opensource.org/licenses/MIT.
+//
+
+== NAME
+
+nng_http_server_add_handler - add HTTP server handler
+
+== SYNOPSIS
+
+[source, c]
+----
+#include <nng/nng.h>
+#include <nng/supplemental/http/http.h>
+
+int nng_http_server_add_handler(nng_http_server *s, nng_http_handler *h);
+----
+
+== DESCRIPTION
+
+The `nng_http_server_add_handler()` adds the handler _h_ to the server
+instance _s_.
+
+If another handler is already added to the server that would conflict
+with handler _h_, then the operation will fail with `NNG_EADDRINUSE`.
+
+If a handler is added to a server, and the server is subsequently
+deallocated, the handler and any of its resources will also be deallocated.
+
+Handlers that are added to a server may be subsequently removed using the
+<<nng_http_server_del_handler.3http#,`nng_http_server_del_handler()`>> function.
+
+== RETURN VALUES
+
+This function returns 0 on success, and non-zero otherwise.
+
+== ERRORS
+
+`NNG_EADDRINUSE`:: Handler conflicts with another handler.
+`NNG_ENOMEM`:: Insufficient free memory exists.
+`NNG_ENOTSUP`:: HTTP not supported.
+
+== SEE ALSO
+
+
+<<nng_http_handler_alloc.3http#,nng_http_handler_alloc(3http)>>,
+<<nng_http_server_del_handler.3http#,nng_http_server_del_handler(3http)>>,
+<<nng_http_server_hold.3http#,nng_http_server_hold(3http)>>,
+<<nng_strerror.3#,nng_strerror(3)>>,
+<<nng.7#,nng(7)>>