[gnome-builder/wip/slaf/xml-symbol-resolver: 20/25] xml-pack: add an OVERVIEW.md documentation file

[Sébastien Lafargue <slafargue src gnome org>]

commit f8b494b633a7ff328bb0b3228d2e51eda91d385b
Author: Sebastien Lafargue <slafargue gnome org>
Date:   Sun Feb 5 23:25:04 2017 +0100

    xml-pack: add an OVERVIEW.md documentation file

 plugins/xml-pack/OVERVIEW.md |   81 ++++++++++++++++++++++++++++++++++++++++++
 1 files changed, 81 insertions(+), 0 deletions(-)
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diff --git a/plugins/xml-pack/OVERVIEW.md b/plugins/xml-pack/OVERVIEW.md
new file mode 100644
index 0000000..51cf2b5
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+# Xml-pack Objects
+
+## IdeXmlAnalysis
+
+A boxed type grouping together an #IdeXmlSymbolTree and the associated #IdeDiagnostics.
+
+## IdeXmlDiagnosticProvider
+
+Get diagnostics for xml/html files from the #IdeXmlService.
+
+## IdeXmlHighlighter
+
+Highlight the matching tags in xml/html files.
+
+## IdeXmlIndenter
+
+Handle the correct indentation in xml/html files.
+
+## IdeXmlSymbolResolver
+
+Get xml/html files symbol trees from the #IdeXmlService.
+
+## IdeXmlSax
+
+A wrapper around the libxml2 sax parser.
+
+## IdeXmlService
+
+A service responsible of fetching and storing the xml/html symbol trees and diagnostics.
+
+## IdeXmlStack
+
+A stack type used by the tree builder to avoid recursive code by using a managed stack.
+
+## IdeXmlSymbolNode
+
+Specific node type for xml/html element.
+
+## IdeXmlSymbolTree
+
+A symbols tree for xml/html files.
+
+## IdeXmlTreeBuilder
+
+A tree builder for xml/html files.
+
+# XML/HTML Symbols tree
+
+## .ui and .glade files
+
+Files with .ui or .glade extension and <interface> as the first node
+are parsed with these specifics rules.
+
+To not clutter the symbol tree, only the following tags correspond to a visible node:
+
+`<template> <object> <child> <packing> <style>`
+
+`<menu> <submenu> <section> <item>`
+
+Specifics processing:
+
+* Collected sub-nodes or attributes shown on the same line:
+
+`<template>` tag: "class" and "parent" attributes.
+
+`<object>` tag: "class" and "id" attributes.
+
+`<child>` tag: "type" and "internal-child" attributes.
+
+`<style>` tag: `<class name=" "/>` sub-nodes.
+
+`<menu>` tag: "id" attributes.
+
+`<submenu>` tag: "id" attribute and `<attribute name="label">` value.
+
+`<section>` tag: "id" attribute and `<attribute name="label">` value.
+
+`<item>` tag: "id" attribute and `<attribute name="label">` value.
+
+## HTML and XML files
+