[BUGFIX] Tests may fail due to PhantomJs not ready (#283)

* [BUGFIX] Tests may fail due to PhantomJs not ready

- PB: Under some systems, Behat tests fails due to the fact the
PhantomJS server is not ready to handle connections.
- FIX: ensure server is running before continuing.
- NOTE: currently use curl to test, if curl is not available, it doesn't
wait

* [FEATURE]Exit after 10s if PhantomJS doesn't start

Note: curl test has been replaced by phing internal http request.

* [BUGFIX] Fix checked port

4444 instead of 8888 set in behat.server-url

phing/tasks/tests.xml

@@ -63,6 +63,10 @@
               passthru="true"
               spawn="true"
               checkreturn="true" />
+        <echo message="Waiting 10 seconds for PhantomJS (http://127.0.0.1:4444) to become available."/>
+        <waitfor maxwait="10" maxwaitunit="second" checkevery="1" checkeveryunit="second">
+          <http url="http://127.0.0.1:4444"/>
+        </waitfor>
       </then>
     </if>
   </target>