patch 9.0.1359: too many "else if" statements in handling options

Problem:    Too many "else if" statements in handling options.
Solution:   Add more functions for handling option changes. (Yegappan
            Lakshmanan, closes #12060)
diff --git a/src/proto/optionstr.pro b/src/proto/optionstr.pro
index 594632e..57b3d74 100644
--- a/src/proto/optionstr.pro
+++ b/src/proto/optionstr.pro
@@ -12,6 +12,7 @@
 char *did_set_backupcopy(optset_T *args);
 char *did_set_backupext_or_patchmode(optset_T *args);
 char *did_set_breakindentopt(optset_T *args);
+char *did_set_isopt(optset_T *args);
 char *did_set_helpfile(optset_T *args);
 char *did_set_colorcolumn(optset_T *args);
 char *did_set_cursorlineopt(optset_T *args);
@@ -23,6 +24,7 @@
 char *did_set_selectmode(optset_T *args);
 char *did_set_showcmdloc(optset_T *args);
 char *did_set_splitkeep(optset_T *args);
+char *did_set_swapsync(optset_T *args);
 char *did_set_switchbuf(optset_T *args);
 char *did_set_sessionoptions(optset_T *args);
 char *did_set_viewoptions(optset_T *args);
@@ -36,6 +38,7 @@
 char *did_set_eventignore(optset_T *args);
 char *did_set_printencoding(optset_T *args);
 char *did_set_imactivatekey(optset_T *args);
+char *did_set_keymap(optset_T *args);
 char *did_set_fileformat(optset_T *args);
 char *did_set_fileformats(optset_T *args);
 char *did_set_cryptkey(optset_T *args);
@@ -96,6 +99,8 @@
 char *did_set_cinoptions(optset_T *args);
 char *did_set_lispoptions(optset_T *args);
 char *did_set_renderoptions(optset_T *args);
+char *did_set_rightleftcmd(optset_T *args);
+char *did_set_filetype_or_syntax(optset_T *args);
 char *did_set_termwinkey(optset_T *args);
 char *did_set_termwinsize(optset_T *args);
 char *did_set_termwintype(optset_T *args);