Docker Compose 1.2.0 RC3 发布

Docker Compose 1.2.0 RC3 发布，测试此版本请使用：

<div class="line number1 index0 alt2"><code class="shell plain">curl -L https:</code><code class="shell plain">//github</code><code class="shell plain">.com</code><code class="shell plain">/docker/compose/releases/download/1</code><code class="shell plain">.2.0rc3</code><code class="shell plain">/docker-compose-</code><code class="shell plain">`</code><code class="shell functions">uname</code> <code class="shell plain">-s`-`</code><code class="shell functions">uname</code> <code class="shell plain">-m` > </code><code class="shell plain">/usr/local/bin/docker-compose</code></div>
<div class="line number2 index1 alt1"><code class="shell functions">chmod</code> <code class="shell plain">+x </code><code class="shell plain">/usr/local/bin/docker-compose</code></div>

此版本相比 RC1 和 RC2 修复的 bug 如下：

When copying a service’s configuration with extends, image and build could come into conflict, resulting in an error, as it makes no sense to have both defined. Each now overwrites the other: if a service with image defined is extended and build is added, the image entry will be removed.
When copying a service’s configuration with extends, if both services defined a multi-value option such as ports or dns, the original value would be completely discarded. They are now concatenated instead.
When a relative path is supplied to build, it is treated as relative to the directory of the configuration file, not the directory that docker-compose is being run in. In the majority of cases, those are the same, but if you use the -f|--file argument to specify a configuration file in another directory, this is a breaking change.