Retire LDAP node classifier docs

The `ldap` node terminus was removed in OpenVox 8; the node terminus
indirector no longer ships it. Remove the docs that still present it
as an available feature:

- Delete nodes_ldap.md ("The LDAP Node Classifier" page).
- Drop its nav entry from _data/nav/openvox_8x.yml.
- Remove the `ldap` node terminus paragraph and its ldap_guide ref-def
  from subsystem_catalog_compilation.markdown.
- Remove the "LDAP node data" reference and its ldap_nodes ref-def
  from lang_classes.markdown.

The repo has no redirect mechanism, so /openvox/latest/nodes_ldap.html
will 404 after deletion — acceptable for a removed-feature page
(precedent: lang_updating_manifests retirement in #270).

Closes #278

Signed-off-by: Michael Harp <mike@mikeharp.com>

Author: miharp

_data/nav/openvox_8x.yml

@@ -341,8 +341,6 @@
   items:
   - text: External node classifiers
     link: "nodes_external.html"
-  - text: The LDAP node classifier
-    link: "nodes_ldap.html"
 - text: Misc. references
   items:
   - text: Settings (configuration reference)

docs/_openvox_8x/lang_classes.markdown

@@ -34,7 +34,6 @@ title: "Language: Classes"
 [declare]: #declaring-classes
 [setting_parameters]: #include-like-vs-resource-like
 [override]: #using-resource-like-declarations
-[ldap_nodes]: ./nodes_ldap.html
 [hiera]: /openvox/latest/hiera_intro.html
 [external_data]: /openvox/latest/hiera_automatic.html
 [array_search]: /openvox/latest/hiera_merging.html
@@ -396,7 +395,7 @@ However, note that:
 
 ## Assigning classes from an ENC
 
-Classes can also be assigned to nodes by [external node classifiers][enc] and [LDAP node data][ldap_nodes]. Note that most ENCs assign classes with include-like behavior, and some ENCs assign them with resource-like behavior. See the [documentation of the ENC interface][enc] or the documentation of your specific ENC for complete details.
+Classes can also be assigned to nodes by [external node classifiers][enc]. Note that most ENCs assign classes with include-like behavior, and some ENCs assign them with resource-like behavior. See the [documentation of the ENC interface][enc] or the documentation of your specific ENC for complete details.
 
 ## Appendix: Smart parameter defaults
 

docs/_openvox_8x/nodes_ldap.md

@@ -18,7 +18,6 @@ title: "Subsystems: Catalog compilation"
 [node terminus]: ./configuration.html#node_terminus
 [plain_node]: ./indirection.html#plain-terminus
 [exec_node]: ./indirection.html#exec-terminus
-[ldap_guide]: ./nodes_ldap.html
 [facts_builtin]: ./lang_facts_and_builtin_vars.html
 [node definitions]: ./lang_node_definitions.html
 [agent_provided]: #agent-provided-data
@@ -108,8 +107,6 @@ By default, OpenVox Server uses the [`plain` node terminus][plain_node], which j
 
 The next most common node terminus is the [`exec` node terminus][exec_node], which will request data from an [external node classifier (ENC)][enc]. This can return classes, variables, an environment, or some combination of the three, depending on how the ENC is designed.
 
-Less commonly, some people use the `ldap` node terminus, which will fetch ENC-like information from an LDAP database. See the page on [LDAP nodes][ldap_guide] for more information.
-
 Finally, it's possible to write a custom node terminus that retrieves classes, variables, and environments from any kind of external system.
 
 ### Step 2: Set variables from the node object, from facts, and from the certificate