[gnome-builder] doc: add howto on search & replace with regex

[Christian Hergert <chergert src gnome org>]

commit be2adde358771101c5763d2edd9709377381e3bf
Author: Christian Hergert <chergert redhat com>
Date:   Mon Jun 12 17:40:32 2017 -0700

    doc: add howto on search & replace with regex

 doc/howto/index.rst              |    1 +
 doc/howto/search_and_replace.rst |   18 ++++++++++++++++++
 2 files changed, 19 insertions(+), 0 deletions(-)
---
diff --git a/doc/howto/index.rst b/doc/howto/index.rst
index 9f128bf..5cd6790 100644
--- a/doc/howto/index.rst
+++ b/doc/howto/index.rst
@@ -13,4 +13,5 @@ Contents
    :titlesonly:
 
    indentation
+   search_and_replace
 
diff --git a/doc/howto/search_and_replace.rst b/doc/howto/search_and_replace.rst
new file mode 100644
index 0000000..85192cc
--- /dev/null
+++ b/doc/howto/search_and_replace.rst
@@ -0,0 +1,18 @@
+##################
+Search and Replace
+##################
+
+Search and replace can be used to replace all instances of a keyword with another form of text.
+To bring up the “Search and Replace” tool, use ``Ctrl+h`` while focused in the editor.
+
+.. note:: If you are using an alternate keyboard shortcut theme, your shortcut might be different.
+
+Enter the search text in the first text entry.
+Enter the replacement text in the second text entry.
+
+.. tip:: The replacement text may contain “regex backreferences” such as ``\1`` and others.
+         See the g_regex_replace_ documentation for more information.
+
+Select “Replace” to replace the next match or “Replace All” to replace all matches.
+
+.. _g_regex_replace: 
https://developer.gnome.org/glib/stable/glib-Perl-compatible-regular-expressions.html#g-regex-replace