Revert "Simplify docs and REAMDE even more"

This reverts commits 8ceb0e8.
and fd97983.

README.rst

@@ -33,8 +33,8 @@ and can be installed via `composer <https://getcomposer.org/>`_:
 Simple example
 --------------
 
-The simplest way to use it is with :meth:`SphinxInventoryParser::parseFromDoc()`
-that creates a :class:`SphinxInventory` object directly from an online documentation,
+The simplest way to use it is with |SphinxInventoryParser::parseFromDoc()|
+that creates a |SphinxInventory| object directly from an online documentation,
 based on its URL (and an optional inventory path).
 
 .. code:: php
@@ -87,6 +87,9 @@ Build scripts
 
 .. Epilog .. ..................................................................
 
+.. |SphinxInventoryParser::parseFromDoc()| replace:: ``SphinxInventoryParser::parseFromDoc()``
+.. |SphinxInventory| replace:: ``SphinxInventory``
+
 .. |License LGPL-2.1-or-later| image:: https://img.shields.io/badge/license-LGPL--2.1--or--later-blue.svg
    :target: LICENSE
 .. |PHP versions tested| image:: https://img.shields.io/badge/php-7.4%20%7C%208.0%20%7C%208.1%20%7C%208.2%20%7C%208.3-blue.svg

docs/usage.rst

@@ -8,6 +8,9 @@ so there are multiple ways to use it.
    :start-after: .. Example
    :end-before: .. Documentation
 
+.. |SphinxInventoryParser::parseFromDoc()| replace:: :meth:`SphinxInventoryParser::parseFromDoc()`
+.. |SphinxInventory| replace:: :class:`SphinxInventory`
+
 Using an existing stream
 ------------------------