This adds support for creating the FISH-BUILD-VERSION-FILE in the CMake
build. A FISH-BUILD-VERSION-FILE is created in the CMake directory
and only updated when necessary.
This reverts functional changes in commit
3bef4a3c1f.
* Annotated tags only should be used for releases - see #3572 for
examples of where we want to use lightweight tags.
See also git-tag(1) on the purpose of annotated and lightweight tags.
* Version numbers are numbers and should not start with a branch name.
The commit ID is embedded in the version and uniquely identifies the
history. `fish --version` and `echo $FISH_VERSION` contain this
information.
Now that we're working on the 3.0.0 major release it is more important
than ever that fish binaries built by developers have version strings
which clearly communicate where they came from.
When calculating the version, we don't need to test for the presence of
.git before running `git describe`. This lets us work properly in a
detached work tree if GIT_DIR is set.
Note: if you have previously cloned the repository, the tags for
previous versions have been edited. Use `git fetch --tags` to
synchronise your local copy.
