docs: update chunking usage docs, minor reorg (#550)

Signed-off-by: Panos Vagenas <35837085+vagenas@users.noreply.github.com>

docs/reference/pipeline_options.md

@@ -0,0 +1,36 @@
+# Pipeline options
+
+Pipeline options allow to customize the execution of the models during the conversion pipeline.
+This includes options for the OCR engines, the table model as well as enrichment options which
+can be enabled with `do_xyz = True`.
+
+
+This is an automatic generated API reference of the all the pipeline options available in Docling.
+
+
+::: docling.datamodel.pipeline_options
+    handler: python
+    options:
+        show_if_no_docstring: true
+        show_submodules: true
+        docstring_section_style: list
+        filters: ["!^_"]
+        heading_level: 2
+        inherited_members: true
+        merge_init_into_class: true
+        separate_signature: true
+        show_root_heading: true
+        show_root_full_path: false
+        show_signature_annotations: true
+        show_source: false
+        show_symbol_type_heading: true
+        show_symbol_type_toc: true
+        signature_crossrefs: true
+        summary: true
+
+<!-- ::: docling.document_converter.DocumentConverter
+    handler: python
+    options:
+        show_if_no_docstring: true
+        show_submodules: true -->
+