[gimp] devel-docs: add some info about libtool versioning to release-howto.txt

[Michael Natterer <mitch src gnome org>]

commit 6acd7e24bbd81218e712e8b20093298e4fdba754
Author: Michael Natterer <mitch gimp org>
Date:   Wed Aug 27 20:42:24 2014 +0200

    devel-docs: add some info about libtool versioning to release-howto.txt

 devel-docs/release-howto.txt |    7 +++++--
 1 files changed, 5 insertions(+), 2 deletions(-)
---
diff --git a/devel-docs/release-howto.txt b/devel-docs/release-howto.txt
index e247019..89cb52c 100644
--- a/devel-docs/release-howto.txt
+++ b/devel-docs/release-howto.txt
@@ -25,7 +25,8 @@
  ( ) Bump the version number to an even micro in configure.ac and
      commit this change. It should be the version number of the
      release you are about to make. Releases always have even micro
-     numbers.
+     numbers. Don't forget to also bump the interface age for stable
+     releases. For devel releases, read libtool-instructions.txt.
 
  ( ) Make dist tarballs:
 
@@ -88,7 +89,9 @@
 
  ( ) Bump the version number (past the tagged version) in configure.ac
      to the next odd micro and commit this change. GIT version always
-     have odd micro numbers.
+     have odd micro numbers. Don't forget to also bump the interface
+     age for stable releases. For devel releases, read
+     libtool-instructions.txt.
 
  ( ) Grab a properly chilled beverage and enjoy yourself.