title: PECL yaml in PHP7
body: <p>Having some issues with pecl yaml in PHP7 <em>(see below for error log)</em>. What I can see on: <a href="https://pecl.php.net/package/yaml" rel="noreferrer">https://pecl.php.net/package/yaml</a> is that there's some RC's for 2.0 that is suppose to cover the issue... I'm currently running the command:</p>
  <pre><code>pecl install yaml &amp;&amp; echo &quot;extension=yaml.so&quot; &gt; /usr/local/etc/php/conf.d/ext-yaml.ini. 
  </code></pre>
  <p>But guess this won't install the RC version. <strong>How do I install the RC?</strong> is there a parameter to supply maybe..?</p>
  <p>I could google the following solution <em>(not tested)</em>:</p>
  <pre><code>pear config-set preferred_state beta
  </code></pre>
  <p>But I guess that this will set a global beta state for all extensions. I only want to install this extension as beta..</p>
  <hr />
  <h3>Error log</h3>
  <pre><code>running: make
  /bin/bash /tmp/pear/temp/pear-build-defaultuserPVGidl/yaml-1.2.0/libtool --mode=compile cc  -I. -I/tmp/pear/temp/yaml -DPHP_ATOM_INC -I/tmp/pear/temp/pear-build-defaultuserPVGidl/yaml-1.2.0/include -I/tmp/pear/temp/pear-build-defaultuserPVGidl/yaml-1.2.0/main -I/tmp/pear/temp/yaml -I/usr/local/include/php -I/usr/local/include/php/main -I/usr/local/include/php/TSRM -I/usr/local/include/php/Zend -I/usr/local/include/php/ext -I/usr/local/include/php/ext/date/lib  -DHAVE_CONFIG_H  -g -O2   -c /tmp/pear/temp/yaml/yaml.c -o yaml.lo
  mkdir .libs
   cc -I. -I/tmp/pear/temp/yaml -DPHP_ATOM_INC -I/tmp/pear/temp/pear-build-defaultuserPVGidl/yaml-1.2.0/include -I/tmp/pear/temp/pear-build-defaultuserPVGidl/yaml-1.2.0/main -I/tmp/pear/temp/yaml -I/usr/local/include/php -I/usr/local/include/php/main -I/usr/local/include/php/TSRM -I/usr/local/include/php/Zend -I/usr/local/include/php/ext -I/usr/local/include/php/ext/date/lib -DHAVE_CONFIG_H -g -O2 -c /tmp/pear/temp/yaml/yaml.c  -fPIC -DPIC -o .libs/yaml.o
  In file included from /tmp/pear/temp/yaml/yaml.c:35:0:
  /tmp/pear/temp/yaml/php_yaml.h:56:40: fatal error: ext/standard/php_smart_str.h: No such file or directory
   #include &lt;ext/standard/php_smart_str.h&gt;
                                          ^
  compilation terminated.
  Makefile:195: recipe for target 'yaml.lo' failed
  make: *** [yaml.lo] Error 1
  ERROR: `make' failed
  </code></pre>