Guzzle 6 conflict with latest google php api client
<p>I've got some issue when trying to install google php api client into my existing php application using composer. I use the following command to install:</p>

<pre><code>composer require google/apiclient:^2.0.0@RC
</code></pre>

<p>The error that I got:</p>

<pre><code>./composer.json has been updated
Loading composer repositories with package information
Updating dependencies (including require-dev)
Your requirements could not be resolved to an installable set of packages.

  Problem 1
    - google/apiclient v2.0.0-RC3 requires guzzlehttp/guzzle 5.2.* -&gt; satisfiable by guzzlehttp/guzzle[5.2.0] but these conflict with your requirements or minimum-stability.
    - google/apiclient v2.0.0-RC2 requires guzzlehttp/guzzle 5.2.* -&gt; satisfiable by guzzlehttp/guzzle[5.2.0] but these conflict with your requirements or minimum-stability.
    - google/apiclient v2.0.0-RC1 requires guzzlehttp/guzzle 5.2.* -&gt; satisfiable by guzzlehttp/guzzle[5.2.0] but these conflict with your requirements or minimum-stability.
    - google/apiclient v2.0.0-RC8 requires google/auth 0.8 -&gt; satisfiable by google/auth[v0.8].
    - Conclusion: don't install google/auth v0.8
    - Installation request for guzzlehttp/psr7 (locked at 1.3.0) -&gt; satisfiable by guzzlehttp/psr7[1.3.0].
    - google/apiclient v2.0.0-RC6 requires google/auth 0.7 -&gt; satisfiable by google/auth[v0.7].
    - google/apiclient v2.0.0-RC7 requires google/auth 0.7 -&gt; satisfiable by google/auth[v0.7].
    - Conclusion: don't install google/auth v0.7
    - google/apiclient v2.0.0-RC4 requires google/auth 0.5 -&gt; satisfiable by google/auth[v0.5].
    - google/apiclient v2.0.0-RC5 requires google/auth 0.5 -&gt; satisfiable by google/auth[v0.5].
    - Conclusion: don't install google/auth v0.5
    - Installation request for google/apiclient ^2.0.0@RC -&gt; satisfiable by google/apiclient[v2.0.0-RC1, v2.0.0-RC2, v2.0.0-RC3, v2.0.0-RC4, v2.0.0-RC5, v2.0.0-RC6, v2.0.0-RC7, v2.0.0-RC8].


Installation failed, reverting ./composer.json to its original content.
</code></pre>

<p>From google php api client requirements it says that it supports guzzle 6. Any ideas what might be the issue?</p>

<hr>

<p>I tried to install <code>google/auth</code> <code>0.8</code> which is the latest, but got similar issues:</p>

<pre><code>- Conclusion: remove guzzlehttp/psr7 1.3.0
- Conclusion: don't install guzzlehttp/psr7 1.3.0
- google/auth v0.8 requires guzzlehttp/psr7 1.2.* -&gt; satisfiable by guzzlehttp/psr7[1.2.0, 1.2.1, 1.2.2, 1.2.3].
- Can only install one of: guzzlehttp/psr7[1.2.0, 1.3.0].
- Installation request for guzzlehttp/psr7 (locked at 1.3.0) -&gt; satisfiable by guzzlehttp/psr7[1.3.0] 
</code></pre>