[glibmm] Makefile.am: Added a manual reformat target, to use clang-format.

[Murray Cumming <murrayc src gnome org>]

commit 6d114bc86dedebb6c5007e7ba1abf8888879939c
Author: Murray Cumming <murrayc murrayc com>
Date:   Fri Feb 26 09:25:37 2016 +0100

    Makefile.am: Added a manual reformat target, to use clang-format.

 Makefile.am  |    4 ++++
 configure.ac |    2 ++
 2 files changed, 6 insertions(+), 0 deletions(-)
---
diff --git a/Makefile.am b/Makefile.am
index bd39e4f..7473185 100644
--- a/Makefile.am
+++ b/Makefile.am
@@ -55,3 +55,7 @@ DISTCLEANFILES = $(filter %mmconfig.h,$(msvc_files))
 
 # Auto-generate the ChangeLog file from the git log on make dist
 include $(top_srcdir)/build/dist-changelog.am
+
+reformat:
+       $(CLANG_FORMAT) -i `find . -name "*.h"`
+       $(CLANG_FORMAT) -i `find . -name "*.cc"`
diff --git a/configure.ac b/configure.ac
index 14809ac..b7f88f8 100644
--- a/configure.ac
+++ b/configure.ac
@@ -129,6 +129,8 @@ AC_DEFINE([GLIBMM_PROPERTIES_ENABLED],[1], [This is always set. This is only for
 AC_DEFINE([GLIBMM_VFUNCS_ENABLED],[1], [This is always set. This is only for backwards compatibility.])
 AC_DEFINE([GLIBMM_DEFAULT_SIGNAL_HANDLERS_ENABLED],[1], [This is always set. This is only for backwards 
compatibility.])
 
+AC_CHECK_PROGS([CLANG_FORMAT], [clang-format clang-format-3.9 clang-format-3.8 clang-format-3.7], 
[clang-format])
+
 AC_CONFIG_FILES([Makefile
                  tools/Makefile
                  tools/gmmproc