BRANCHING_AND_TAGGING

Here's my attempt to document the process for branching and tagging releases 
of codec2 and freedv.

1/ Update the version in CMakeLists.txt in both codec2-dev and freedv-dev to
   the intended release version.

   Ideally the version in -dev would be greater
   than the version branched or tagged but as we can't predict the next release
   we settle for them at least being the same.

   Minor changes that don't break API/ABI compatibility (including bug fixes)
   should only cause a PATCH level bump.

   Minor changes that do break API/ABI compatibility should bump the MINOR
   version.

   MAJOR bumps should be reservered for significant milestones or major changes
   to the UI or other changes that could be considered disruptive to the end 
   users experience.

2/ Copy the source to a new branch directoy.

   The directory name should only include the MAJOR and MINOR version number.

   (from the freetel directory)
   $ svn cp codec2-dev codec2/branches/<MAJOR>.<MINOR>
   $ svn cp freedv-dev freedv/branches/<MAJOR>.<MINOR>

3/ Go into each branch directory and make the necessary modifications.

   This could include Debug->Release changes (if set)

   Specifically in the case of freedv we need to change cmake/BuildCodec2.cmake
   to checkout codec2 from the appropriate branch instead of codec2-dev.

4/ Tag a release

   Similar to the previous step, except we copy from the branch dir to the tag
   dir. 

   $ svn cp codec2/branch/<MAJOR>.<MINOR> codec2/tag/<MAJOR>.<MINOR>.[PATCH]
   $ svn cp freedv/branch/<MAJOR>.<MINOR> freedv/tag/<MAJOR>.<MINOR>.[PATCH]

   The patch level should only be specified if it exists (non-zero).

   Why both branch and tag you ask? While SVN doesn't enforce it, the idea 
   behind tags is that they are immutible, meaning once you tag a release it
   doesn't change, instead you would update the branch with whatever changes
   are needed and tag a new release (bump the minor version).

5/ Export and archive the releases

   codec2:
   $ svn export codec2/tags/<MAJOR>.<MINOR>.[PATCH] \
       codec2-<MAJOR>.<MINOR>.[PATCH]
   $ tar acf codec2-<MAJOR>.<MINOR>.[PATCH].tar.xz \
       codec2-<MAJOR>.<MINOR>.[PATCH]
   freedv:
   $ svn export freedv/tags/<MAJOR>.<MINOR>.[PATCH] \
       freedv-<MAJOR>.<MINOR>.[PATCH]
   $ tar acf freedv-<MAJOR>.<MINOR>.[PATCH].tar.xz \
       freedv-<MAJOR>.<MINOR>.[PATCH]

   This could probably be somewhat automated through a bash script, I'll work
   on that when I have some free time.

6/ Upload to files.freedv.org

   I'm not sure who all has access other than me. We'll address this later.