Add example and test case for job configuration expansion.

First suggestion by @nsoranzo and second was easy once example was added to advanced config.

config/job_conf.xml.sample_advanced

@@ -442,6 +442,13 @@
             <param id="docker_enabled" from_config="use_docker">false</param>
         </destination>
 
+        <!-- Templatized destinations - macros can be used to create templated
+        destinations with reduced XML duplication. Here we are creating 4 destinations in 4 lines instead of 28 using the macros defined below.
+        -->
+        <expand macro="foohost_destination" id="foo_small" ncpus="1" walltime="1:00:00" />
+        <expand macro="foohost_destination" id="foo_medium" ncpus="2" walltime="4:00:00" />
+        <expand macro="foohost_destination" id="foo_large" ncpus="8" walltime="24:00:00" />
+        <expand macro="foohost_destination" id="foo_longrunning" ncpus="1" walltime="48:00:00" />
     </destinations>
     <resources default="default">
       <!-- Group different parameters defined in job_resource_params_conf.xml
@@ -515,4 +522,15 @@
         -->
         <limit type="output_size">10GB</limit>
     </limits>
+    <macros>
+        <xml name="foohost_destination" tokens="id,walltime,ncpus">
+            <destination id="@ID@" runner="cli">
+                <param id="shell_plugin">SecureShell</param>
+                <param id="job_plugin">Torque</param>
+                <param id="shell_username">galaxy</param>
+                <param id="shell_hostname">foohost_destination.example.org</param>
+                <param id="job_Resource_List">walltime=@WALLTIME@,ncpus=@NCPUS@</param>
+            </destination>
+        </xml>
+    </macros>
 </job_conf>

lib/galaxy/util/xml_macros.py

@@ -127,7 +127,6 @@ def _expand_macro(element, expand_el, macros, tokens):
     _expand_macros(expanded_elements, macros, tokens)
     macro_tokens = macro_def.macro_tokens(expand_el)
     if macro_tokens:
-        print macro_tokens
         _expand_tokens(expanded_elements, macro_tokens)
 
     # HACK for elementtree, newer implementations (etree/lxml) won't

test/unit/jobs/test_job_configuration.py

@@ -128,6 +128,12 @@ class JobConfXmlParserTestCase( unittest.TestCase ):
 
         assert env_dest.env[ 3 ][ "execute" ] == "module load javastuff/2.10"
 
+    def test_macro_expansion( self ):
+        self.__with_advanced_config()
+        for name in ["foo_small", "foo_medium", "foo_large", "foo_longrunning"]:
+            print self.job_config.destinations.keys()
+            assert self.job_config.destinations[ name ]
+
     # TODO: Add job metrics parsing test.
 
     @property