Create aliases for export region functions

lisp/ox-ascii.el: Create alias `org-export-region-to-ascii` for
`org-ascii-convert-region-to-ascii`.
lisp/ox-html.el: Create alias `org-export-region-to-html` for
`org-html-convert-region-to-html`.
lisp/ox-latex.el: Create alias `org-export-region-to-latex` for
`org-latex-convert-region-to-latex`.
lisp/ox-md.el: Create alias `org-export-region-to-md` for
`org-md-convert-region-to-md`.
lisp/ox-texinfo.el: Create alias `org-export-region-to-texinfo` for
`org-texinfo-convert-region-to-texinfo`.
doc/org-manual.org: Change commands from "*-convert-region-*" form to
the "org-export-region-to-*" aliases.  Add function index for aliases.

doc/org-manual.org

@@ -16400,34 +16400,40 @@ Some export backends include commands to convert a region of Org
 formatted text to another format, such as HTML or LaTeX.  The
 conversion replaces the original source.  Here are such commands:
 
-- ~org-ascii-convert-region-to-ascii~ ::
+- ~org-export-region-to-ascii~ ::
 
   #+findex: org-ascii-convert-region-to-ascii
+  #+findex: org-export-region-to-ascii
   Convert the selected region into ASCII.
 
-- ~org-ascii-convert-region-to-utf8~ ::
+- ~org-export-region-to-utf8~ ::
 
   #+findex: org-ascii-convert-region-to-utf8
+  #+findex: org-export-region-to-utf8
   Convert the selected region into UTF-8.
 
-- ~org-html-convert-region-to-html~ ::
+- ~org-export-region-to-html~ ::
 
   #+findex: org-html-convert-region-to-html
+  #+findex: org-export-region-to-html
   Convert the selected region into HTML.
 
-- ~org-latex-convert-region-to-latex~ ::
+- ~org-export-region-to-latex~ ::
 
   #+findex: org-latex-convert-region-to-latex
+  #+findex: org-export-region-to-latex
   Convert the selected region into LaTeX.
 
-- ~org-texinfo-convert-region-to-texinfo~ ::
+- ~org-export-region-to-texinfo~ ::
 
   #+findex: org-texinfo-convert-region-to-texinfo
+  #+findex: org-export-region-to-texinfo
   Convert the selected region into Texinfo.
 
-- ~org-md-convert-region-to-md~ ::
+- ~org-export-region-to-md~ ::
 
   #+findex: org-md-convert-region-to-md
+  #+findex: org-export-region-to-md
   Convert the selected region into Markdown.
 
 The in-place conversion is particularly handy for quick conversion of

lisp/ox-ascii.el

@@ -2098,6 +2098,8 @@ a communication channel."
   (let ((org-ascii-charset 'ascii))
     (org-export-replace-region-by 'ascii)))
 
+(defalias 'org-export-region-to-ascii #'org-ascii-convert-region-to-ascii)
+
 ;;;###autoload
 (defun org-ascii-convert-region-to-utf8 ()
   "Assume region has Org syntax, and convert it to UTF-8."
@@ -2105,6 +2107,8 @@ a communication channel."
   (let ((org-ascii-charset 'utf-8))
     (org-export-replace-region-by 'ascii)))
 
+(defalias 'org-export-region-to-utf8 #'org-ascii-convert-region-to-utf8)
+
 ;;;###autoload
 (defun org-ascii-export-as-ascii
     (&optional async subtreep visible-only body-only ext-plist)

lisp/ox-html.el

@@ -3969,6 +3969,8 @@ to convert it."
   (interactive)
   (org-export-replace-region-by 'html))
 
+(defalias 'org-export-region-to-html #'org-html-convert-region-to-html)
+
 ;;;###autoload
 (defun org-html-export-to-html
     (&optional async subtreep visible-only body-only ext-plist)

lisp/ox-latex.el

@@ -4199,6 +4199,8 @@ command to convert it."
   (interactive)
   (org-export-replace-region-by 'latex))
 
+(defalias 'org-export-region-to-latex #'org-latex-convert-region-to-latex)
+
 ;;;###autoload
 (defun org-latex-export-to-latex
     (&optional async subtreep visible-only body-only ext-plist)

lisp/ox-md.el

@@ -764,6 +764,7 @@ this command to convert it."
   (interactive)
   (org-export-replace-region-by 'md))
 
+(defalias 'org-export-region-to-md #'org-md-convert-region-to-md)
 
 ;;;###autoload
 (defun org-md-export-to-markdown (&optional async subtreep visible-only)

lisp/ox-texinfo.el

@@ -1993,6 +1993,8 @@ command to convert it."
   (interactive)
   (org-export-replace-region-by 'texinfo))
 
+(defalias 'org-export-region-to-texinfo #'org-texinfo-convert-region-to-texinfo)
+
 (defun org-texinfo-compile (file)
   "Compile a texinfo file.