1. Magit 2.1

Spacemacs is now compatible only with Magit 2.1 and later, be
sure to *update your packages* (at least Magit).

2. Helm

Helm input pattern is now displayed in its header instead of the
minibuffer.

3. Git layer

The `git` layer has been split into two layers: `git` and `github` so
the layer variable `git-enabled-github-support` is deprecated, you
have to *add the layer `github` in your dotfile*.

The `git-gutter` has been replaced by `diff-hl`. This package is in
the new layer `version-control`, be sure to *add this new layer to
your dotfile*.

4. Auctex layer

The `auctex` layer has been renamed `latex`, be sure to *update your
dotfile* if you use this layer.

5. Erlang/Elixir layer

The erlang/elixir layer has been split into two layers `erlang` and
`elixir`, be sure to *update your dotfile* if you use these layers.

6. Key bindings changes

Projectile key bindings changes:
~SPC p e~ is now ~SPC p r~ (recent files),
~SPC p R~ is now ~SPC p G~ (regenerate tags),
~SPC p r~ is now ~SPC p R~ (replace).