inveniosoftware/invenio — pull request #2048 by greut (2014-08-06 09:36:52+00:00)
Title: formatter: fix RSS generation

Before:
```python
>>> from invenio.modules.formatter import format_record
>>> format_record(20, of="xr")
Traceback (most recent call last):
File "/opt/invenio/invenio/modules/formatter/engine.py", line 504, in format_record_1st_pass
**kwargs)
File "/opt/invenio/invenio/modules/formatter/engine.py", line 387, in format_record
out_, needs_2nd_pass = format_with_format_template(template, bfo, verbose)
File "/opt/invenio/invenio/modules/formatter/engine.py", line 715, in format_with_format_template
evaluated_format = xslt.format(xml_record, template_source=format_content).decode('utf-8')
File "/opt/invenio/invenio/modules/formatter/engines/xslt.py", line 284, in format
temporary_result = xslt(xml)
File "xslt.pxi", line 585, in lxml.etree.XSLT.__call__ (src/lxml/lxml.etree.c:153659)
File "lxml.etree.pyx", line 327, in lxml.etree._ExceptionContext._raise_if_stored (src/lxml/lxml.etree.c:10196)
File "extensions.pxi", line 824, in lxml.etree._extension_function_call (src/lxml/lxml.etree.c:142042)
File "extensions.pxi", line 610, in lxml.etree._wrapXPathObject (src/lxml/lxml.etree.c:139824)
File "extensions.pxi", line 606, in lxml.etree._wrapXPathObject (src/lxml/lxml.etree.c:139772)
XPathResultError: This is not a supported node-set result: False
Failed to perform the XSL transformation.
u''
```

After:
```python
>>> from invenio.modules.formatter import format_record
>>> format_record(20, of="xr")
u'
\n

Charge creation and reset mechanisms in an ion guide isotope separator (IGIS)

\n http://0.0.0.0:4000/record/20\n \n Arje, J\n Sat, 05 Jul 2014 09:45:35 GMT\n http://0.0.0.0:4000/record/20\n Finland Univ. Dept. Phys.\n Jul 1982\n
\n'
```