doc: Fixups to #43419 which added operators in the docs

- Escape the method names as e.g. `operator <` is invalid XML.
- Add a hack to merge all String % operator definitions for each Variant type
  as a single one with `Variant` argument type.
- Add support for the new qualifiers in makerst.py.
- Drop unused `doc_merge.py`, seems to date back to when we had all the
  documentation in a single `classes.xml`.

1 files changed, 2 insertions, 0 deletions

diff --git a/doc/tools/makerst.py b/doc/tools/makerst.py
index ed147f31cd..5335116c8a 100755
--- a/doc/tools/makerst.py
+++ b/doc/tools/makerst.py
@@ -1042,6 +1042,8 @@ def make_footer():  # type: () -> str
         ".. |virtual| replace:: :abbr:`virtual (This method should typically be overridden by the user to have any effect.)`\n"
         ".. |const| replace:: :abbr:`const (This method has no side effects. It doesn't modify any of the instance's member variables.)`\n"
         ".. |vararg| replace:: :abbr:`vararg (This method accepts any number of arguments after the ones described here.)`\n"
+        ".. |constructor| replace:: :abbr:`constructor (This method is used to construct a type.)`\n"
+        ".. |operator| replace:: :abbr:`operator (This method describes a valid operator to use with this type as left-hand operand.)`\n"
     )
     # fmt: on