[gtksourceviewmm] Change ABI from gtksourceviewmm-4.0 to gtksourceviewmm-5.0

[Murray Cumming <murrayc src gnome org>]

commit 9320ea07f038d3f25d0539b7389eb7540bc5b6e0
Author: Murray Cumming <murrayc murrayc com>
Date:   Tue Dec 4 13:48:57 2018 +0100

    Change ABI from gtksourceviewmm-4.0 to gtksourceviewmm-5.0
    
    There isn't actually a gtksourceview-5 (targetting gtk+ 4) yet,
    so there won't be much activity on this git master branch,
    but this clearly shows that the master branch is for gtkmm 4,
    not gtkmm 3, and not for gtksourceview-4 (which uses gtk+ 3).
    
    See the gtksourceviewmm-4 branch, which uses gtksourceview-4 and
    gtkmm-3.0.

 configure.ac | 4 ++--
 1 file changed, 2 insertions(+), 2 deletions(-)
---
diff --git a/configure.ac b/configure.ac
index 32939fa..c41b42e 100644
--- a/configure.ac
+++ b/configure.ac
@@ -1,4 +1,4 @@
-AC_INIT([gtksourceviewmm], [3.21.3],
+AC_INIT([gtksourceviewmm], [4.91.1],
         [http://bugzilla.gnome.org/enter_bug.cgi?product=gtksourceviewmm],
         [gtksourceviewmm], [http://projects.gnome.org/gtksourceviewmm/])
 AC_PREREQ([2.62])
@@ -14,7 +14,7 @@ AM_MAINTAINER_MODE
 AC_ARG_VAR([ACLOCAL_FLAGS], [aclocal flags, e.g. -I <macro dir>])
 
 MM_PREREQ([0.9.8])
-MM_INIT_MODULE([gtksourceviewmm-4.0])
+MM_INIT_MODULE([gtksourceviewmm-5.0])
 
 # Copy the mm-common .pl scripts into docs/,
 # and use them from there,